speedo trouble

So i swapped motors in my 91 got the new motor from a 96, transmission and T case.
the VSS i guess that's what its called was different, so i put the old one in.
No speedo, i put the newer one in still no speedo.

What should i do?? could it be something in the tailshaft of the T case?
I really would have no problem with this but it's my GFs dd

Just putting it in is not enough,---it must engage the gear on the shaft. The sensor has notches and the housing has numbers that corospond with the # of teeth on the speedo gear.Rotate housing to the correct area and the hold down fork will engage the notch.

Wayne