I'm setting up my fuel system and have a Paxton FPR theres 4 ports on it. I know one if for a gague, one is blocked off, and there is an in and out, one on the bottom and one on the side, just trying to figure out which is which and ive googled it and gone to paxton, no luck so far

 

the one on the side is your in (the fuel line comiing off the secondary fuel rail)
the one on the bottom is an out (your return line gets hooked up here)
the blocked off one is on the pressure side aswell.... a sending unit for a electric gauge can be hooked up here (for example)
the one one the front is....like u said.........for a mechanical gauge that can be viewed from the engine bay
breakdown:
3 pressure side fittings
1 non pressure side fitting for the return line
you should also have a fitting for a vacuum line that can be hooked up to any pressure source ( ie a vacuum fitting on the uim)
i have a fuel lab regulator but they are all the same

 

thanks, exactly what i was looking for