Dave, I'll take a stab here that you have a rusted transmission drive shaft female yoke that is stuck onto the PDS (primary drive shaft)
I'll also take a stab that the PDS at the FWD end is rusted into the splines of the drive coupler, if you cannot seperate the engine from the Flywheel Cover.
There is a solution for both, but it aint an easy one. I've helped several people over the years with this same thing.
Often a part of the "universal" drive shaft must be sacrificed in order to get the transmission out of your way.
This may involve cutting it off FWD of, or Behind, one of the bearing crosses.
Once out of your way, you can rig up a chain slide hammer and go to work on pulling this off of the PDS.
As for the front section (the PDS in the drive coupler), there is a way to bore a hole into the F/C for access to the junction where these two join.
If the PDS is rusted tightly onto the coupler, this access may allow you to drive on it, to help break this rust up.
One person bored his hole in a location that allowed him to loosen each of the "drive coupler" bolts that secure it to the flywheel.
Once loose, the engine seperated from the F/C...... and the engine was free to come out.
This left the drive couple attached to the PDS, and within the F/C......... and I can tell you, this gives us much better access to remove it.
Andy of these parts that may become damaged are avialable from a salvage yard that I am very close to. None of which will break the bank, should you need to replace them. There are lots of these older parts available in areas where Volvo Penta is big! And I'm in one of those areas here in Oregon.
Assuming that you are removing the transmission ONLY at this time........ what ever you do, DO NOT attempt to remove the four transmission clamping collar bolts until you get the transmission off and on the bench.
More on that later if that's the case.
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