OK so I know that the proper way to adjust lash is to use different length pushrods. What would happen if I shimmed under the fulcrum if I needed a shorter rod or ground some off of the fulcrum if I needed a longer rod?

 

You probably could grind them some, but it would have to be done on a surface grinder. You can usualy shim them .03 safely. but you should check the geometry afterwards. It's important that the rocker tip sweep the valve tip evenly or you will have excessive rocker, valve tip, & guide wear.

 

You can get shims from Crane cams to raise the fulcrum. Push rods too if you know the length. In the past you could get push rods from Ford in .030 longer/shorter.