What engine, AHU, ALH, BEW?
As for the AHU and the ALH, both of them dont run fuel pumps, they draw a suction from the tank and a check valve, you will have MAJOR issues, MASSIVE LEAKS from the IP if you run that sort of pressure and you probably will damage the QA.
Best thing you can do is pull the fuel tank, remove the pump and put a line to the bottom of the tank with a fuel pick up sponge and if your doing some performance stuff you can run a walbro pump at 11PSI, they are EPIC pumps and wont restrict the flow if it stops working so you can turn it off if need be.
the problem with diesel vs gas in regards to reducing pressure and temps is that gasoline drops temp MASSIVELY when it atomizes but diesel does not, well not nearly as much as a gas engine that relies on spark vs heat and compression on a diesel. Having a return from a pressure regulator especially one going from 52PSI to at most 10 is just going to heat up the diesel and wear out the pump, not to mention that the pump probably wont last too long running a MUCH thicker fluid.
could it work with a cheap regulator, yes, is it a good idea, not so much. I would highly suggest you put a 4 row cooler on the return to the tank if you do run it like that.
