Thanks again and appreciate your help. Placed the EGR back on yesterday. Is holding vacuum when closed @ 10 in Hg with timing advanced to 15 degrees BTDC. Funny thing, when opening the EGR with a Mityvac, the engine stalls. Got a major vacuum leak somewhere.

Will be going looking for leaks today once again. Borrowed an advancing timing light and checked to check timing. When the timing is set on 15 degrees, and advancing the light to get a TDC reading, I'm off by 5 degrees according to the light. Think chain stretch is causing the vacuum problem?