What are some of the most overlooked modifications that people overlook when building/modifying a classic Mustang, especially those mods for comfort and/or performance. Include the reason why one should consider the particular mod.

i.e. Overdrive transmission, electric fan, Ipod hook-up capable radio, quality aftermarket speakers, etc...

 

One of the biggest improvements in automobile tuning was the elimination of points through solid state iginition. The second is fuel injection.

Pertronix makes a system to replace the points that is cheap and works great.

Fuel injection is much more involved, but the carbs went out years ago for a reason, they can be a pain.

For me Fuel Injected 5.0 / 5 speed in these older mustangs are a fantastic way to go, parts are cheap, there are kits available and it fits without any modifications.

 

I would have to say the Shelby drop. Relocating the UCA mounting points fixes the crappy stock suspension geometry, giving you better handling and responsiveness. It's essentially free, and will make more of a difference in handling than any one other part you can replace in the front end.

 

First and formost, focus on safety..... high back seats, 3 point seat belts, disc brakes, collapsible steering columns, brighter headlights and taillights...etc