Cityhix, any cheap fuel pressure gage will work fine. The order of the system should be ~~ fuel filer separator ~ fuel pump ~ polishing filter ~ gage ~ carb.
The gage will let you know what the carb "sees" and that is what feeds it!! Once installed and any trouble rears it's head a quick look at the gage showing pressure means look elsewhere or perhaps inside the carb as the "delivery" of the fuel is OK.
Dave Neptune
