i have a holley fuel pressure regulator and i dont know how to adjust it their is a nut on the top that looks like it can be adjusted but im not sure please help me out

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92 Camaro RS
305 TBI
T-Tops
DynoMax Cat-Back Exhaust
Gutted Cat
Hypertech Street Runner Chip
K&N open element
Custom Interior
Window Tint
Prestige Alarm
Foglights

JVC El-Kameleon Head Unit(w/ remote)
Pyramid 6 x 9's
(bass blockers)
Jensen 5 1/4's
2- 10" Kenwood Tornado Subs
Pyramid 600 Watt Amp
Best ET: 15.976 @ 86.01 mph
reaction time: 0.479
60 ft: 2.269