Dan,
Good luck with your project. You will be very happy when it is all finished. I just completely rebuilt my 77. I guess I should say the guys up at Mt. Logan rebuilt it. Every part on it with the exception of the frame is new. I too went with the Terra Comp fiberglass tub, fenders, grill and hood. You are welcome to look at the work that they did. It turned out amazing! Those guys are unbelievable at what they do and it might save you some time and effort down the road. I bought a lot of parts off of ebay from NASCAR teams including the axles, differentials, etc.
JT