could it be as simple as adjusting or swapping the pressure regulator ? i can't see there being much difference in the intank pump. not that i haven't been wrong before !   The earlier ones had a return system. Not exactly sure when the returnless system was incorporated. 94 maybe?
"Follow me the wise man said, but he walked behind"
'92 D250 Club Cab CTD, 47RH conversion, pump tweaks, injectors, rear disc and hydroboost conversion.
'74 W200 Crew Cab 360, NV4500, D44, D60 and NP205 divorced transfer case. Rear disc and hydroboost conversion.
2019 1500 Long Horn Crew Cab 4WD, 5.7 Hemi.
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