I was looking on the web and ran across a picture that made me second guess which one is the fill port. The picture I saw had someone writing do not use on the bolt to the right of the pto cover. I just picked up my gen 1 yesterday and want to top off the fluids and such.

Getrag g360 image by alwaysworking_photos on Photobucket

 

I would take off the shifter and fill thru there so you can add an extra quart, the getrag lives longer with 4.5 quarts instead of 3.5. I would use synt. 5w-30

 

I did more research on several forums and I just removed the top bolt from the pto cover and put in 5 qts no problem.

The transmission does make a bit of a rattling noise when lugged or even just idling in 3rd and 4th. 3rd is barely doing it but 4th is pretty dominate I'd say up to 1500 or so.

 

My getrag lets me know im going to slow for the selected gear especialy in 4th. so i just keep the rpm's up and it sounds fine.