I'm pretty sure that the 93-94 CV's still had the AOD. Could be wrong though. If this is indeed true, then the trans. you have came from a 97, which would indeed have the 4R70W that your car had from stock.
The early 4R had serious issues w/ the TC and the roller clutch. The 94/95 T-bird trans. is known to have these issues as well, and nothing short of switching to Mercon V fluid and adding a cooler will help save it from what I've seen, and even then it's iffy.
The 97's got an updated design of the roller and while it was vastly improved over the early 94/95 design, it has still been proven inferior to the one-way mechanical diode that is in the 99+ transmissions. This is the reason that most people here swap to the newer style trans. when their's finally dies. IMO, it's not worth modding a stock early trans. in hopes of it ever holding any power other than stock.
I'm sure there have been freak occurances of people making their older trans. last at above stock HP, but I'd be willing to be that there is more that have had the stock trans. die behind the stock motor, me included, lol...
These are highly engineered precision vehicles, the first step in diagnosing the problem is to strike the suspected offending part sharply and repeatedly with a blunt object, then re-test.