I found an unimaginable situation while swapping in a 5 speed gear box in place of the automatic gear box my 180B came from factory.
This is a 1974 180B with an L20B motor and an automatic gear box. I am swapping in a 5 speed gear box that came from a 1973 Datsun 180B . The problem I found, never heard about something like this , the L20B engine crankshaft end is 88.mm in size. The recess on the 5 speed gear box flywheel is only 80.mm. How is this posible??
Never heard of anything like this, is this a common situation ???
I am going to have to machine the flywheel to accept the larger 88.mm crankshaft.
Need some insights.

Cheers.

Have you checked that their is not a spacer on the back of the crankshaft to mate to the auto?
1200 AUTOS come with a spacer on the end of the crank to fit the box so it may be the same situation.
See if you can give the end a few light taps on the edge with a dead blow mallet or similar to see if it comes loose.

Thanks CarJunkie. You were right on the spot. I tapped the end of the crankshaft and saw it moving!!!
Thanks mate.

Cheers!!!

Cool! Glad to be of assistance! Nissans/datsuns are one of the best cars for interchangability and i knew it couldn't be a major drama to sort it out.
Now, for some pics of the happy driver and their new found gear shifting enjoyment!