Well some new info to add. I didn't mention before that I had also been in contact with a tech from Carter. Long story short is he told me the Precision pump was for a GM 454 and I should not use it as damage to the cam may happen. So I pulled out the pump and sure enough the arm is quite a bit different. So I decided to combine the two and make one that works--hopefully. I tried to put the old arm on the new pump but couldn't seem to get them off--didn't try real hard because i didn't want to damage anything. I then decided to use the guts out of the new and put in the old--basically a rebuild. However, I couldn't figure out how to get the diaphragm out--I think you might need to take the arm out to get it out. So since my initial problem was leaking at the other gasket, not the diaphragm, so I swapped everything but the diaphragm in. Not sure if it works yet didn't get time today to try and get it started. If/when this pump goes out think I will go with an electric pump, would be much cheaper than the other replacement. So, if you get the Precision pump, or the carter one that is the same as this Precision one, and use it, as is, in anything but the 454 then damage may occur. Just wanted to let you know.