mechanical rockers

Sorry I'm nowhere close to help but things don't have to be new to set it right with a feeler gauge. I assume you must have a solid lifter cam, correct? Cause hydraulics set to zero lash. The main thing is you just need to have the engine in the turned to the right spot to set them. Here's a link to a chart that shows where to have the engine to set each valve.

http://www.moparts.org/Tech/Archive/motor/14.html