I managed to crock myself a month and a bit ago stupidly trying to lift a transaxle out of my car without an engine hoist (did some damage internally somehow, not a bad back!) so I haven't been able to do anything with the engine proper, but I have sold most of the 3.0 24v bits now, except the cam covers.
And, I picked up an original 116 GTV 2.5 v6 crankshaft for a song, so thought I'd share the comparison between the 2.5 v6 24v crankshaft outand the original 'long' 2.5 12v shaft.
Suffice to say never the twain shall meet! Creating an extra shim for the flywheel and creating an extra bearing for the front cover (in place of the 24v's oil pump drive) would be a ridiculous amount of work and would probably result in a heavier, weaker crankshaft with some seepage from the front cover, so as effectively non-interchangeable as the block and heads.
Which also raises the question - since creating a shim to fit the earlier 'long shaft' flywheel to a later engine would put the shim further away from the bearing (this increasing the mechanical force and risk of the shaft being out of balance) than the original crankshaft (which effectively has the shim cast right next to the rear bearing), would this mean using the earlier type flywheel with the later type crankshaft could possibly lessen engine life a little?