Here's some helpful photos of the mount spacers and pumps.
QUESTION: What year, make and model chassis are you working with?
This is the pump we are looking for, this one is not suitable to rebuild.
Just realised some long forgotten person had fitted a narrow belt alternator ( albeit chrome) along with incorrect matching narrow belts , which was throwing me off. The pumps are regular 8RT wide belt. So have to now find a matching wide belt alternator pulley.
Possibly looking at speedway. Stock 50 merc with 3 carbs, yes stock distributor will need an upgrade too to get the correct advance.
What is the alternator anyway?.
Here's a GM alternator with wide belt pulley. Pumps are 8RT.
Here's some sources.
https://www.speedwaymotors.com/GM-Alternator-5-8-Inch-Wide-Alternator-Belt-Pulley-Plain,1868.html
and
https://www.bing.com/search?q=wide+...EDSAQg4MTQ5ajBqNKgCALACAA&FORM=ANAB01&PC=HCTS