Wierd, it is all Mercruiser stuff in there.

From what I saw the only non-mercury part was the small caged bearings on the clutch shaft. The upper case is supposed to be really strong but it still has a "pressed" tower, it's about a 3/4" deeper than a standard XR tower. The upper cap seems stout but I didn't have the patience or the $$ to keep wasting. $10K in drive repairs was enough for me to make a switch.

While it's apart, it might be a good idea to replace the bearings in the drive gears with the max machine caged bearings. They apear to be a heavier bearing. I never got to use them because I sold it.

Jason,
after it ran out the top hole did u put the plug in and continue to fill it till the bottle filled up?? Or did u top off the bottle? I let the bottle drain with the drive and then fill it from the bottom. If you did it this way. Not sure why there was an air pocket at the top. There is a natural flow to the oil in the drive and there maybe a blockage in that path.. oil is pumped up to the top thru the top cap and down on the upper gear..
I asked Dock Holiday to fwd u an email I sent him, with some suggestions..

Hope this helps.

I filled the drive from the bottom up & then topped off the bottle.
Are you saying to fill it up to the top of the plug & then coninue to fill it till the bottle is full?

Yes! When you see fluid start to come out from the top plug
stop and let it sit for a few mins so any air bubbles can come up. Then put the plug in, Take the cap off the fill bottle,
continue to fill from the bottom til the bottle is full. I always
put the boat in and check the fluid after I have idled out for
a while. (before getting on plane). The fluid is thick and even
after doing this you may have to add a little to the bottle. hope
this helps. Timmy.

Yes Jason,
As Timmy said.. fill till it comes out of the plug then plug it and continue filling till it comes up in the bottle. Wont hurt to let it burp some before you continue to fill. And another thing, you could tilt the drive up and let it burp. .. Under the lower gear, where the tower is, an air pocket can form there.. Although I have never had a problem with it. I have seen drives melt down the lower gear bearing and tower.
I always fill as tfarmer said, but dont wait for it to burp. But my bottle is empty and the cap is off so it may be burping thru the bottle.
D*ck