Need Holley One Barrel Recommendation

3 carbs were used that I know of - Carter BBS, Holley 1920, Holley 1945. Many say the latter is best and most efficient. The BBS is probably less fuss and easier to trouble-shoot. I recall that Holley sold an Economaster model for the slant in the 1980's, which you sometimes see on ebay. Before that, consider if you want to change to a 2 bbl or 4 bbl manifold, since that gives many more carb options. A few have made custom MPFI, which is the ultimate fueling.