Help 1982 300d injection pump and Alda connection

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Hi can anyone give me a picture or description of the 300d 617 injection pump. Is this the Bosch series (M)? Question does the the collar which holds the nut for the ALDA have an o- ring for sealing oil? And what size is the hex wrench for tightening the collar for the 27 mm nut which holds the ALDA? It must have a hole for the plunger shaft. Finally, is there a nut inside the injection pump which holds the threaded collar which attaches to the ALDA? Or does it just thread on to the top plate of the IP?
Thank you