Many thanks for doing that research in the 700 section regarding the B21a/AW71 interface, I've cut and pasted it here so when I'm trying to find it next spring I stand a good chance of doing so:
Researched as promised Alan :
https://www.volvopartswebstore.com/p...4/6842013.html
Scroll down and click the "What this fits" tab - you will get a long list of 240, 740, 760, 940 & 960 models that it fits. Anything up to ~1986 will be B2xX, after will be B2x0X where x is the second digit of the engine size in dl (eg 21 is 2.1L, 23 is 2.3L) and X is the suffix A, E, F etc.
Short version is your existing driveplate/flexplate will be fine to bolt the TC onto.
Alan