Upgraded steering wheel: A factory woodgrain wheel is an improvement over the plain-Jane installed in most Mustangs. From the aftermarket, Grant Products offers a number of wheels that provide the right look and feel.
Tilt-steering column: Just right for obtaining the perfect steering position.
Sequential taillights: Simply cool, and easy to install too. Mustang Project now offers a wider, Shelby-style version for '65-'66 Mustangs.
Air-conditioning: Gotta have it in a restomod. Classic Auto Air offers several systems, from stock and original to daily driver.
High-zoot stereo: Custom Autosound offers a number of head units that fit the early Mustang instrument-panel openings, but from there you can add a trunk-mounted CD changer and speakers, including CA's kick-panel versions and Rear Seat Driver for hardtops with 10-inch woofers and an amp.