FWIW Paul, have you considered going with shaft rockers to eliminate the stud girdle? I built a 565 a few years back and wanted to run the short Ansen covers w/o spacers, so I turned to Crower and a set of their stainless shaft rockers which fit with a low profile. Here's a few pics of them and the short covers I used. They sure keep the valve train stable while allowing the elimination of spacers and girdles. Just a thought?
