The 94-97 7.3 engine uses a piston (or plunger) stile pump, just like the rockers the piston goes up and down as the cam goes round! The pump has a low side and a high side, it pumps both ways up and down this causes a slite drop in pressure(your gage is too sensitive so it seems to jump)!
Your pressure seems fine to me. I would check the screen I listed above because that is what caused my truck to fall off on top end and caused it to shutter when lugging. You might also check the HPOP pressure, if the HPOP
(High Pressure Oil Pump) is not providing enough pressure it will cayse the same problems.
By the way the 7.3 in these years used a single shot (From factory) injector they only need 24psi to start and idle, but i set mine at 50 psi at idle with my size injectors! It is an Aeromotive A1000 pump and dual inlet regulator, as Locomoton said he has listed a site for you. It was cheaper to replace my factory system than to rebuild it! But I would check the cheaper stuff out first like the screen! GOOD LUCK!
96 F-250 4X4,DP Tunner, EZmod, up graded IDM, custom drive shafts, staight axle up grade, 5-speed,head studs, bps bypass, dual HPOP's, AFE Filter, aeromotive fuel system, tubes, springs, oringed, copper head gaskets, 5" stacks (all chrome), south-bend dd clutch, H2E big spinny thing, some hugh-jazz injectors, 3" body lift (had to fit the turbo in), homemade traction bars fromt and rear, blood sweat & lockers!!
Four different trucks had to die to make this one!!!!!!!!!!!Thats why we call him FRANKEN STROKE!
Too much fuel, and not enough money
Sled pulling in NC,TENN,VA,and anywere else theyll let us!!!!!
P.S. Dont be afraid of the sawzall! It can fix anything!