Seized motor on donor truck!! no rotation ..old 235 4 speed chev

We are trying to get the clutch plate pressure plate and flywheel,out of a donor truck ,2 ton ,it had a 4 speed in it we removed that , this gave us access to 4 bolts on the pressure plate around the bottom ,cover removed, the top bolts we cannot get too
We have removed 4 bolts from the (bellhousing) Gearbox to engine housing to try to remove it, still wont come apart is there more than 4 bolts holding it to the motor ..2 just behind the motor and 2 near the flywheel accessable only from under inside the housing .
Any suggestions on how to get the clutch gear out when the motor cannot be rotated
Dumb question i know , but frustrating yes ,as the donor truck is 1 hour away out in scrubland there is not a lot of workshop tools out there to make life easy
Thanks in advance