Were the valve covers plumbed back into the intake manifold, or did you just have small air filters capping them off?
Plumbed back like stock. I tried to make that truck as factory looking as possible. It had PCV, EGR, cats etc. If I remember right the passenger's side valve cover had a hose that went to the intake tube between the air filter and throttle body and the lower intake at the very back of the motor had a wire mesh screen with a PCV valve sitting right on top of it with a hose that went to... I forget. I think the upper intake behind the TB but can't remember exactly now and don't have my pics handy to reference.