How much trouble is it to bolt the trans up to the bell housing and then install the shifter and try it? If you support the trans, you can even start the engine to get the syncros spinning.
If all goes well, then install the T/C and driveshaft and skid.
If it doesn't shift, then you can drop it back out and open the case.
Perhaps you can rent a transmission jack to make the job easier. Harbor Freight has a transmission jack for $100.00
Good Luck, L.M.