Farmtrac 555 injection pump

[Dallas Goodman]

I am trying to help a neighbor repair his late father’s farmtrak 555 dtc and need help with the injection pump. I am looking for someone to rebuild it or at least a good parts diagram and source for parts?
I saw an old thread here that mentioned pumpguysc but can’t seem to find them now.
Specifically there is a little piston(oil pump?)cover missing. Any information would be appreciated!

 

[TractorTech]

Welcome to TBN!

@thepumpguysc is his handle.

Parts book, but doesn't show much on Bosch pump: https://www.farmtracpartsonline.com/_files/ugd/819289_eec45a53b297466a87e628805d8d1e1e.pdf