HRC 216 self propel broke...again

I repaired my self propel last season thanks to help from Robert. It was a roll pin from the transmission shaft. The retaining clip had broke.

Now the self propel has stopped again but this time it seems to be a problem at the connection closet to the transmission box. The major problem is I can not figure out how to access that area to see what the issue is.

Can anyone give advice on how to access this spot on the transmission/shaft area and possible problem?

Thanks.

Tim

HRC 216 self propel broke...again