Hey, Azizi:

You're in my neighborhood now :-) If this list is pre-1980, Luther Vandross's first top 40 hit was Never Too Much, which hit the top 40 in November of 1981. (The Gospel Messengers sang for Luther Vandross once by the way, but he never sang for us..) You'd probably find the Clovers and the Costers listed as "doo wop" (Dumb term) rather than soul.

Let's Stay Together by Al Green was a #1 R&B hit in 1971 and certainly should be on the list. Maybe you overlooked it.

My list of favorite pre-1980 R&B and Soul hits is much longer than 100.

Jerry