66 Formula S barracuda
Hello, Welcome!!
Yes, they had the rear resonator in the rear for the 66 Commando (Formula S) engine. The exhaust has probably been changed (!).
Yes, solid lifters.
The wheels/tires you'll have to get from someone else. Yes, 14X5.5" rims on the Formula S.
Sounds like a good car. You should check the fender tag to insure it is a true Formula S. You can also look for obvious things like the 150 mph speedo and the tach in place of the performance indicator. Also, the Formula S had a sway bar in front. On the engine, the finned valve covers and four barrel are indicators. But, best to check the Fender Tag... a 7 under the F is the Formula S code.
Have fun!!