Main seal questions for 3.0 & 3.2
 

The #1 bearing has thrust-flanges to control axial play of the crank.
The crank has flanges to fit precisely into the #1 bearing leaving a groove/channel for the 2 oil holes in the case.
When removing the main seal, the outer thrust-flange of the crank should be visible.
When removing the old seal, how deep is the recess in the case? xx mm?
How thick is the main seal? xx mm?
Is the case from a 3.0 different from a 3.2 in the main seal area?

Expert comments, and measurements, much appreciated.

Why is the thrust-flange from the crank not visible in this picture?

http://forums.pelicanparts.com/uploa...1149953277.jpg

The thrust flange is the other side of the crankshaft part that has the holes in it. I don't know if there is a different depth for the seal in 3.0 vs 3.2 engines but I don't think so. You install the seal flush with the outside of the case. Don't press it in to the bottom of the recess. The holes in the case are drain holes for the oil that comes out from between the thrust bearing (number 1 main) and the crank flange.

-Andy

Thanks Andy:
Found the answer.
The confusion arose because the design of the crankshaft changed after '78 from 6 to 9 holes meaning: There is no more seperate thrust flange on the crank and the main seal became larger.