Lagging fuel pressure increase under boost. 94 Mustang Cobra. My oil pressure gauge is fuel pressure

Just did this video to show what is happening. 94 Mustang cobra 373 cu in. ON3 turbo kit. I have a 340 L Aeromotive fuel pump and regulator. Peak boost 10 and 10.5 psi respectively. Intake pressure taken directly to the regulator port. Can't figure out the problem.