This kirban is maybe 20 years old, so who knows what shape it is in. I don't smell gas, but I'll have to grab a small vac hand pump and test.
Pump needs to be changed regardless. It's 30 years old.
I definitely noticed this issue slightly a while ago, but now it's more prominent. If I got WOT the FP spikes to 39psi and then drops off even under full load to 30-34psi. Seems strange.
Regardless, new pump, filter and rebuild of regulator on tap. I figure I'll do a couple local drives to burn down gas and see if I can troubleshoot now. I can't even merge into the highway now as I just can't go WOT. It falls on its face.