MYSTERY SOLVED!!!
OK, I went out there with some spray, cleaner, compressed air and a wire brush. I located the flat area abutting the tranny bell housing, between the starter and the firewall (there was a heater hose sitting right on top of it so it was difficult to find in the first place).
There was a thin coat of rust on the plate area so I proceeded to brush (holding the heater hose up the whole time). Put the flashlight on the area still nothing. Brushed again. Flashlight, nothing. Third time brushing, flashlight I could begin to see the faint outline of a number. OK, so after several brushings, air, and spray cleanings I managed to get the very faint imprint of a VIN, and I mean faint. I noticed this with the diff too. The stamping on the diff was so faint I could barely see it.
Given the awkward placement of this VIN plate and the fact that it is so faintly stamped that even a thin coat of rust could totally obscure it, I do not feel bad at all about not finding it the first couple of times. I do appreciate all of the help.
Oh, and by the way it is the original engine - cool.