Yes you can. You'd want a liquid filled gauge for a rail-mount.
With your RT, is screwing with fuel pressure even something you need to do (vs just opening up the injector pulsewidth, etc)? I'd rather not screw with something which will be adapted to (like fuel pressure).
With a tweecer you want the pres. stock, I have a guage to watch the pres. though. Its a liquid filled guage mounted on my cowl. I watch it for pres. drop and whe on the bottle for pres. drop.