Have a friend who is an old race car mechanic. Accomplished settings by trial and error using his expertise. Had the truck out last night and experienced just a slight warbling at heavy acceleration in both 1st & 2nd. Will do some fine tuning again next week and report.
Previously had a 600 cfm Holley on my old 235 & current 261. 235 had limited vacuum; 261 has plenty. Of course, on either engine--way overcarbed, but had both running strong with #70 jets and aggressive accelerator cam. Mpg was pretty pathetic at about 9 mpg. Son's 454 does better.
