What “No-Cut” Really Means on NA/NB Dashboards

On most U.S.-market NA and NB Miatas, the center bezel, nicknamed the “tombstone”, was never designed for a modern full double-DIN screen. While some owners make true 2-DIN work with trimming or specialty bezels, that’s not the goal here. If you want Apple CarPlay without taking a Dremel to anything visible, you’ve got three practical routes: a portable CarPlay screen that mounts on the dash or glass, a single-DIN solution that fits the stock opening (either a flip-out screen or a single-DIN chassis with a floating display), or a modular/off-chassis design that separates a thin front screen from a small “brain” you can hide deeper in the stack. The stock tombstone remains intact in all three paths.

Path A ,  Portable CarPlay Screen

Portable CarPlay units suction-mount to the windshield or stick to the dash, draw power from the cigarette lighter, and hand off audio to your existing radio through AUX or a short-range FM signal. Setup is nearly tool-free, you keep the OEM head unit and plastics, and you can uninstall in minutes. Sound quality is best when you use a wired 3.5 mm AUX input; FM is convenient but can add hiss. Wireless pairing is straightforward, auto-reconnect usually works once you’ve set it up, and many units accept an optional reverse-camera input. This path suits minimalists and anyone preserving factory aesthetics for shows or resale.

Path B ,  Single-DIN CarPlay Without Trimming the Tombstone

The factory opening is single-DIN friendly, so two styles slot right in. A flip-out single-DIN uses a standard 1-DIN chassis that powers a motorized 7-inch screen; you wire it like any normal head unit and verify the screen clears the shifter in 1st/3rd/5th before final mounting. A floating-screen single-DIN keeps the 1-DIN body but hangs a larger 8.95–10.1-inch display on an adjustable arm; position it to avoid blocking HVAC knobs or vents. Many current floating units support wireless CarPlay, while flip-outs are commonly wired CarPlay over USB. This route delivers a modern touchscreen experience with stock plastics and a totally reversible install.

Path C ,  Modular Screen With a Hideaway Brain (Near-OEM Look, Still No Cutting)

Modular designs split a slim 6.8-inch touchscreen from a compact electronics box. The thin panel mounts up front where a shallow 1-DIN frame would sit, and the “brain” tucks behind the radio cavity or under the center stack on Velcro or a small bracket. You get a tidy, almost factory-looking screen without widening the opening, plus the flexibility to service the hidden box later. CarPlay typically runs over USB for this style, but the payoff is the cleanest, most integrated look while keeping the tombstone stock.

Parts List by Miata Generation (No Factory-Wire Cutting)

For a plug-and-play connection, use a vehicle-specific radio harness. Many NA and early NB1 cars accept a harness that mates to the OEM radio plugs and provides color-coded aftermarket leads. Later NB1/NB2 cars use a 24-pin style, same idea, different connector. If a previous owner cut the factory plugs, you can restore with replacement pigtails or identify wires by color and function with a multimeter before rebuilding the connections neatly.

If you’re installing a single-DIN chassis, a simple trim kit with a storage pocket keeps the opening tidy and maintains the stock dimensions. The idea is the same across NA and NB: fill the unused space without altering the bezel.

Bench-Loom the Harness

On the bench, join the vehicle-specific harness to your head unit pigtail by function: Yellow to constant 12 V, Red to switched/ACC, Black to a solid ground, and Orange/White to illumination or dimmer if the unit supports it. On non-Bose cars, match speaker pairs color-to-color. On Bose NBs, cap the amplified speaker leads and instead route the head unit’s front and rear RCA pre-outs to the Bose interface. Wrap the loom in Tesa tape, leave a service loop, and avoid bulky butt connectors where space is tight.

Floor-Test Before Mounting

Set the radio on the passenger floor and plug everything in. Confirm the unit powers with the key, CarPlay connects, balance and fader behave (non-Bose), and the display dims with the lights if your illumination line is connected. Catching mistakes here saves you from tearing the stack apart twice.

Antenna, Mic, and USB Routing

The NA/NB antenna is a straightforward plug. Mount the Bluetooth microphone high on the A-pillar or headliner area rather than on the gauge hood to avoid wind noise. Route your CarPlay USB into the cubby or glovebox; even on wireless units, a tucked USB is useful for firmware updates and backup wired sessions. Right-angle USB pigtails help where glovebox clearances are tight.

Mounting Without Cutting

For flip-out and floating single-DIN units, use the included sleeve and the factory side brackets, adding a rear support strap if your roads are rough. Mock the screen’s tilt, height, and fore-aft so it clears HVAC knobs and the shifter through all gears, then tighten everything. For modular screens, mount the slim panel at the front opening and stick the hidden brain behind the lower stack or above the footwell with Velcro or VHB tape, leaving enough slack in the loom for future service. Reinstall the tombstone last, confirming nothing is under tension and the screen face clears the bezel.

Tools and Consumables That Keep It Tidy

Plan on plastic trim tools, Phillips/JIS drivers, a 10 mm socket, and DIN keys if you’re removing an OEM radio. For wiring, use a decent soldering iron and heat-shrink or high-quality crimps, plus Tesa harness tape for a factory-like wrap. Have a multimeter ready for continuity and voltage checks, a fresh 1.5 V battery for speaker identification if needed, and some Velcro or VHB tape for mounting a modular brain. A short right-angle USB extension is handy when routing through the glovebox.

Common Problems and Fast Fixes

If a Bose car powers up but has no sound, you probably fed the Bose amp with speaker-level power; switch to the head unit’s RCA pre-outs through a proper interface. If the battery drains, double-check that Yellow is on constant 12 V and Red is on switched/ACC, those two being swapped is a classic mistake. If the screen hits the shifter or blocks HVAC, loosen the cage or arm and re-index height and tilt before you button up. And if the factory plug is missing because a previous owner hacked the harness, either restore the OEM pigtail or rebuild cleanly after confirming each wire’s function with a meter.

Why We’re Not Pushing True Double-DIN

The entire point of this guide is getting CarPlay without modifying visible plastics. While a true double-DIN can be done with trimming or special bezels, the cleaner, reversible options are portable, single-DIN flip-out, single-DIN floating, or modular off-chassis units that respect the stock tombstone.

Quick Wiring Map for Your Diagrams

Power the head unit with Yellow to constant 12 V, Red to ACC, Black to a solid chassis ground, and Orange/White to illumination if supported. On non-Bose cars, connect speaker pairs through the harness and verify polarity during the floor test. On Bose NBs, cap the speaker-level outputs and run the RCA pre-outs into the Bose interface feeding the factory amp; use the head unit’s remote-turn-on to wake the interface and amp. With that layout, you get modern CarPlay in an NA/NB while keeping the tombstone exactly as Mazda molded it.