As I read all the responses to your "dilemma" a thought came to mind. Someone said he might, (if i got this correctly) get (if the price is right) another AW70 for a sort of "spare". Good thought. Just adding my 2 cents here tho>> I had occasion to look for another AW70 trans for our '89 wagon, but luck steered me to an AW71L, with actual 125K on it from a newer 940 wagon that had been broadsided just enough to call the brick totaled.

The ‘one owner since new’ brick belonged to the wife of a reputable Volvo shop owner nearby. He wanted $100 for it, a steal, and he gave me a great deal on the AW70 swap from our '89. New kick down cable of course, new fluid etc.. Being said, I would suggest don’t limit your search to only an AW70. Keep your eye out for an AW71L, as apparently AW71L’s from 940s work also. That “L“, “lock-down” feature, does feel solid. Good luck.