No engine codes or lights (93 is pre OBD) Temperature seems normal, No engine light, coolant, oil light, nothin. Actually I am on the Vineyard (Cape and Islands) so highway is not an easy option. I can only go 45-50 for about 5-6 miles and then turn around. "Beater Run"??? don't follow...high and low revs or just flat out. Is running the engine in D3 with higher RPMs an option? I may not have allowed time for the additive to work properly, they do warn that emissions can spike during the cleaning process.
http://www.rxp.com/gaskicker.htm

The second shop mentioned a possible leak in the header or "A" pipe. The inspection shop has not mentioned it.

thanks for the quick reply