No experience with Pypes exhaust but to answer your last question, yes, Big Blocks have the same exit format on stock manifolds. L/S pipe will have a 90 & R/S pipe will have a 45. I'd call them (pypes) directly and discuss. Offer to send pictures too! Had a problem kinda like that with a set of Thorley Headers for my truck & pictures was the only way to resolve. Be aware though too if your engine & trans mounts are shot, the whole assembly will sit lower in the frame and bring the pipes closer to the ground. Ground Up is a reputable company, any issues ask for Kenny! Good Luck!