You picked a doable project. It is a LOT easier to get parts for 60s Mustangs than 60s Mopar C-bodies.
You probably know all the big players, but while I am not a Ford man, I did get into take care of the computers at Mustangs Unlimited in Connecticut back in the 90s. restoring 60s Mustangs was a thing THEN (the 60s Mopar C-bodies were still being used for Demo Derby fodder), so I am sure the industry is extremely well-developed now.
What do you have in it? 289? 351 Cleveland?
Actually I’m sorta manufacturer agnostic. I have 2 (’37) Chevy trucks, the Mustang, and a Dodge Durango. I always wanted to do a Mustang and finally got to a position where I could rationalize investing in one.
This is my first Ford and I’m learning as I go. The car was campaigned as a low-rent dragster by the PO. It came with a built 351 Windsor, C4, and 4:11 gears. It’s scary fast! I’m changing the gear ratio and swapping to an 4-sp AOD - making more of a highway car out of it and restoring the interior to resto-mod (updated gauges, cruise control, decent stereo).
I’ve completely replaced the brakes - right down to the hard lines and fittings as well as upgrading to 4-wheel power discs. I replaced every bit of suspension and steering and upgraded to power steering.
Next up is repairing the rotted floors and then the body work. It’s pretty clean so that should go quick.