All good advice from Bob S. The only things I would add is to make sure you have the right manifolds and generation of f body manifolds. 1st gen. f-bodies use a rear outlet on the pass. side and a center outlet on the drivers side. If you have the wrong ones you can rough fit them and see if you have the room for a custom bend pipe. I always use high temp rtv on all my exhaust connections especially the manifold ball connection. When buying the hardware make sure and get the brass/bronze nuts. And lastly use high temp nickel anti seize on all bolts and studs and make sure you coat not only the threads of the manifold bolts but also the whole length of the shoulder as most manifold bolts rust/seize in the manifold and not in the head. p.s. make sure and look them over really good for hairline cracks before investing any time in them.