I purchased a 68 fastback a few months ago with the 390cuin V8 powering the thing. It has about 450Hp and is real fun to drive.
Doing a 4 wheel disc brake conversion and some modern suspension parts and power steering as well in about 2-3 weeks. Also doing a seat drop as I only just fit in the thing, but when that's done it will be a good reliable car, that does 30L/100km
The car is in pretty good condition after a full restoration in 2000 and the mustang club are very active here in Vic.
Hope you get a happy buyer and I'm sure they will love the car.