Help with Ford 3930 PTO leak

[LondonDave]

I have a 92 Ford 3930 2wd with the manual speed transmission. I have a leak coming out of the bottom of the cover plate that the PTO shaft comes out of. I've removed the bolts and when I start to pull the cover off the shaft comes with it. I've read about how on some models a bearing will drop off when you pull the shaft out and then you'll have to split the back of the tractor to get it back on. I've attach a pic of what my PTO looks like and a link to what I think is the parts diagram for my tractor. I'm guessing it's #4 that I need to replace to stop the leak and it's #10 that I'm concerned about. It looks like it will stay in the back side of the cover plate but I don't want to find out the hard way that it won't.

I'm also wondering where the vent tube that is seen on the left side of the pic attaches. I can't find anywhere that it would go into or on.

Parts diagram here...

Official New Holland Online Parts Store and Online Parts Catalog for New Holland and Ford Tractors.

Thanks

Dave