I myself have smashed a pin or two down upon reinstalling. Make sure the pins are all straight and clean. The other thing that comes to mind is if the flywheel (or flex plate) was installed properly. I have seen one other car come into the shop that wouldn’t run and the careless tech had tightened the flywheel up after not having it clocked properly on the dowel. Last thing. When the intake camshafts were removed, were they marked for A.bank and B bank and put back in the correct heads?