I got a response to my email from Advance Adapters. The information they gave me is that it is not a simple swap. Here are the links they provided me:
Mechanical Clutch Linkage Adapter: $28.87
https://www.advanceadapters.com/prod...-bellhousings/
96 and up NV4500 bell housing adapter kit: $418.20
https://www.advanceadapters.com/prod...llhousing-kit/
Or 93-95 NV4500 Adapter kit: $438.48
https://www.advanceadapters.com/prod...llhousing-kit/
"Note: This bellhousing assembly can also be used with the SM465 4 speed transmissions."
The local transmission guy I talked to about this said the used NV4500 transmissions around here go for about $1,000 from a junkyard, but they might come with a 1 year warranty.
Looks like $500 is the typical core charge for transmission rebuilders, with $2K for an upgraded NV4500 plus shipping and tax, plus add about $500 for the adapter stuff. I am nut sure that my stock clutch will work, based on what I am reading.
I have heard and read that you can just replace the SM465 with an NV4500 and it is a simple bolt in operation but there is conflicting informaton.
Also, I would think I would need a new shifter and maybe a cutout modification of the transmission tunnel hole.
With a new driveshaft required I think this swap could easily be in the $4K range or more.