81 Clutch replacement

[Eeffinger at conestogac.on.ca (Edward Effinger)]

Greetings.
We're in the thick of changing the clutch on the '81S and finding out
that the clutch/trans does not match the Bentley.
 
We've got a 210 mm clutch vs the stock 190 mm and are about to
replace the release bearing and half shaft oil seals as well as the main shaft seal.
 
The trans case seems to be from 1986 and has the following number on the plate of the bellhousing  FN27052.

Just wondering about the origin of this part.
 
Also, we didn't mark the flywheel alignment before removal.
How do we best recover from this?
 
Thanks
Ed