Fuel pressure

Holley needles will handle 7-10 psi but are finicky if you don’t have a good filter. But don’t assume you have a problem with pressure if you don’t have one. Is there fuel dribbling out of the boosters at idle? Yes? You have too much fuel pressure and it’s pushing past the needles. No? The needles are working and you have other tuning problems. If you’re lean at idle you likely don’t have pressure problems. Get the main jetting sorted out for cruise afr and tune the power valve (and pv channel restrictors) for WOT throttle afr.