I was able to repair the busted threaded portion of the reverse shaft discussed above by drilling and tapping the shaft while the transmission was still in the truck. I also confirmed what the Muncie guru's were telling me, the original OEM shaft design was not a screw in stud.
Numerous sources told me that the shaft is hardened, and I believe it is, but not very hard. Drilling was fairly easy, tapping was a bit unnerving, but successful nonetheless.
The repair was made easier by the exhaust routing I did quite a while ago. By simply unbolting the exhaust from the headers and hangers I was able to access the transmission easily.
http://i645.photobucket.com/albums/...%20Transmission/DSCF1918_zpsc3f69e74.jpghttp://i645.photobucket.com/albums/...%20Transmission/DSCF1920_zps6cb5b006.jpg
