Rut Row. These don't like to be regulated to a certain psi. They like to flow. Hmmm. You can get a hobbs pressure switch to be Normaly Closed and route the ground through it and plumb it in the fuel line (like in my pic up there). They you can set it for about 12-14psi and it will shut the pump off at this pressure. However this is all easily done if you've done it before. Otherwise,,,,, Can you send the regulator back and get a different one with a return?
I run the 11110 that's rated at 1000lbs at 45psi (but it goes to 120+psi) and is diesel marine rated. Never an issue in 7 years now. CAT filter before, CAT filter after.