My swap was done by the Fiero Factory. '91 4.9, Caddy ECM, Caddy 4T60E. I've removed it from the car at least twice, since then. The most recent time was when I swapped in a ~'93 Beretta Getrag, in place of the 4T60E. Although the ratios are not ideal, the 5 speed swap made all the difference in the world.
I am looking at swapping the Caddy ECM for a 7730, at some point. But I only know one person who has done it. It's pretty much sorcery and witchcraft at this point. And it's not a huge priority to do. That being the case, progress is slow.
I will try to answer any questions that you may have.
In case I lose track of this thread, please feel free to shoot me an email or PM, if I don't answer here.