TACONV

I recently dropped an LS1 into a 68 C10. I had plates made and was able to use standard 350 motor mounts. I want to put long tubes on it but dont know of any application for LS1 that comes ready to bolt. I lined up a set of stock 05 GTO manifolds to check for clearance. The clearance issue is with the number one and two cylinders and the motor mount support brackets that bolt to the frame and cross member. Do any of you know of an application that I might try?

Thanks in advance