I am looking to add a fuel pressure gauge to my engine. Can anyone tell me what the inlet size is on a marine Quadrajet? I am not near my boat so I can't go look but I would like to order up my parts so I can install it when I get home. Also the inlet and outlet on a MK IV 502MAG mechanical fuel pump are 3/8" correct? Thanks for the help!!!

Anyone?

TM
I cant remember the fuel line size but what you might look at is the merc had a drilled fuel line fitting for testing fuel pressure in quadrajets as in you remove the large fitting holding ther filter and refitted the merctool.
You could make that a permanent swap and connect your gauge there?
I'm talking a few years ago so maybe NLA now, anyway give it a try.

Thanks I will look into that.

3/8th line if std

I'm not sure which fitting you're talking about. The fitting on the fuel line itself is a 3/8 flare, the fitting that goes into the carb is a 1"x20 thread. (the fitting in the picture is to go from the one inch fitting to a -6 A/N)

I just so happened to have all those parts on the kitchen counter, so I just took the pics.

THANKS!!! That is what I am looking for I was not sure if it was a 7/8" or 1" fitting it looks like the larger one was used from 1974 and up. What I wanted to do was have a hard line out of the carb to a fitting that has a gauge port then from that fitting to the fuel pump run a stainless braided flex line. Do you see anyway of this working? I have been looking through Summit online and have yet to find what I think I need. It is a pain in the ass trying to plan stuff when I can not go out and look at what is there. Down side of traveling for work I guess.