Hey!! I have a 88 GMC 1500 4x4 I've just recently had the heads an all the gaskets replaced but the guy said the valves still need adjusted a little more so I'm trying to figure out how exactly I would go about it?? I've been told to start it w/ the valve covers off an the truck running but not so much more detail the turn here an turn there. Honestly I'm mechanically declined when it comes to the inners of a vehicle. Any advice will help. Thanks!!