say the hell away from the CHP 5.1 stroker. they use a 3.625 bore. no good.
the GT crank has 6 or 8 bolt flywheel holes(depending on windsor/romeo) and is nodular iron. The Cobra crank is a forged steel 8 bolt crank. the cobra crank is by far the best piece on the entire car, bar none.
I have eagle rods and CP pistons. Scat is a very well respected ohv brand and i don't know much about their 4.6 rods but id say they are the same forging as the eagle/manley rods.
if you get them, make sure they have arp 2000 rod bolts.
Ross pistons are not my favorite, but others seem to like them. If you are planning for boost, remember to run a bit looser endgap on the rings.
get some fed mogul race main and rod bearings, arp main and head stud, and the billet oil gears.
oh yeah, when you have your block machined make sure they use torque plates and have the main caps studded down. The aluminum blocks like to flex. Oh and also see if they can line hone it to make sure the caps are all of equal size since that is very important with the Fed mogul bearings.
good luck
forged motors are fun