Okay, So have the primary side in pieces replacing all the bearings, races and oil seals to fix the oil leaks.

I noticed that the transmission sprocket was loose on the shaft - it looks like the mainshaft nut backed off a little at some point in time (I guess that small allen bolt did its job and kept it all in though).

I have cleaned up the sprocket and spline and noticed there is some wear on the spline.  When I dry fit the sprocket onto the spline there is some rotational slop when i grab the gear and turn it left and right.

Question:  Just how much slop is acceptable?

replace the sprocket @least with a good brand , not zodiac crap , when fitted load sprocket to drive load & tighten with 620 loctite