I installed an aem regulator with sl55 pump and high filter. The pressure at the gauge on the aem in the rear is saying 80 but when hooking up a fuel pressure gauge to the fuel rail it's saying 58. I have did my research said the pressure should be at 58. Has this happened to anyone else.

 

Did you replace your fuel filter? The factory fuel filter has an internal pressure regulator.

Les

Edit: I re read your post and see you changed the filter.

 

Hard to understand how you have things hooked up. The SL55 pump will supply 80psi, as that is what it was intended to do with the V8 engine. You want 58-60psi at the rail.