47RE swap (photo ID)

Even with the 90 adapter I don't think the OE speedo cable will reach, as mine was about 6 inches short and I had to get an 80 inch cable.
Hard to tell from the pics, but that may very well be the 46RH, and I can see the plug, but not enough to tell the number of pins. (3 pins is an RH lockup)
That also may very well be a diesel trans due to the 6 lugs on the converter.
All it takes to use a diesel trans is to change the governor for a gas one, and they are heavy duty as well but the converter wont fit the standard gas engine flex plate.

More trees.:D

The 42RH barely fits in the tunnel with no floor mods, but the bigger ones need more real estate.
Thanks for the advise on the 42RH and it’s relative size compared to the tunnel. I will look for a core and built it up.