Bob - not frustrated, nor intending to be terse; simply attempting to convey information; sorry you took it the other way.
Pin gauges are wonderful, but a 1~60 drill bit set will get you close enough in this case; most folks have one of these.
SOME of the FLAPS will loan a fuel pressure gauge, but not a common thing.
All of us can guess, but if we guess wrong; and you use our guess as a fix, it costs you money, not us.
The money NOT wasted in guessing will help you acquire test equipment.
Another thought: locally in this area, every podunk town (and I happily live in one) has a cruise-in every 4~6 weeks during the summer. If you have them in your area, attend, make a friend. Sometimes a friend with tools and knowledge, AND a supply of your favorite beverage can be a much more enjoyable Saturday than the TV schedule.
And 4 psi is marginal to too much with the correct fuel valve, way too much for the wrong one.
Stay with it, you will get it fixed.
EDIT: JW - you type faster than I
Jon