I have the same issue with my 496" RB stroker. It was a ball at first but really a PITA to cruise in. I changed the headers back to manifolds, de-cammed, took off the 6 pack in favor of a 750 vacuum carb setup on a TM7, replaced the tach drive distributor with a stock vacuum advance unit, pulled the 727 and 3800 convertor in favor of a 4 speed, and replaced the 4.10 with a 3.23. It is a lot more pleasureable now, but I think that I should still change the big valve heads and TM7 out this winter. The "street race" performance has take a major hit, but I haven't honestly had a real street race in 40 years or so.