Every shop has a prefrence and supports what has worked for them. If Bruce (WE) or transfixleo spoke up (both are tranny guys that stop in from time to time) they may disagree with Steve. I would do what the guy backing the tranny says to do. (good advice with any mechanical part or parts if you want the warrantee honored)
I may be wrong here but I recall transfixleo doesn't like using the radiator core at all. I know this gets real confusing to guys like you and I, just wanting something that's gonna work.
As far as my choice being a 700r4, I already had a TH400. That made the install of the 700r4 easier. I read a lot about the 2 trannys in the mags as well as looked through the archives and 2 years ago 2004r's were thought to be the weaker of the two although I think it was the cusp or turning point and guys like Bruce started surfacing with some inovative mods that produced stronger 2004r's than in the past. I believe Bruce and his shop actually are producing in-house the state of the art 2004r performance pieces needed to make a killer OD tranny. I digress!!
I found a local tranny guy that came highly recomended to me. He learned about building trannys in a performance shop but when he went into business for himself he got out of the performance side because the market was too small. He does conversions as well as builds and had just finished converting 100 or so older chevy work trucks from TH400's( or ?) to 700r4's for some large business. His prefrence was the 700 and I went with that!! I did use Steve's shop for the shiftworks stuff and his TV made ez and a converter. I got lots of support from him and recomend him highly. Many here have personal dealings with Bruce and I feel he is also a stand up business guy and tranny builder!! I don't have knowledge of transfixleo's shop but can say he always speaks professionally here and his advice seems solid.
My builder felt the radiator cooler was fine for my application but I added an external cooler and he wasn't opposed.
Ultimatly you need to select the right shop or person that you feel can do the job. Once you do stick with their recomdations as they are the ones that will back you if there is a problem!!
I lean toward Steve as you have a need to to keep from making major modifications and from the do it yourself side of things he has packaged the conversion into kits taking the fuss out of doing it. It's easy to get a new drive shaft and radiator and set the factory parts aside for safe keeping...
"The '69, the '96 & the club
[This message has been edited by DjD (edited 01-18-2002).]