To save weight I decided to replace the original glass with racing window nets. And if you don’t have windows you don’t need door locks.
I signed up for the Time Attack race series at the local track and promised the organizers I would install a 6-point roll bar before the first event. I had a local shop install Hooker headers and a Flowmaster exhaust to get some more power from the stock 289 V8. Loved the headers and the exhaust but got ripped off by the garage who did the work - I was so annoyed I decided to do everything I could myself from then on. That’s probably why I love the Mustang so much now, I’ve wrenched every bolt on that old car.