there is a valve on your passenger side fuel rail. this at the front, and looks like a valve stem from a tire. I just hooked up a pressure gauge my dad had around his garage that read at least 50 psi. The only issue I had was finding a braided line the same size threads. it should read around 40 psi
If you dont have access to a pressure guage you can use a pen to stick in that hole, it should squirt fuel out. it wont be a lot. It always a good idea to mount a fuel pressure guage on that rail anyhow.
You also need to remove the vacuum line off of the regulator and cap the black hose with your finger. Use a real gauge that is accurate and is made for this application. Start the car with the gauge already in place let it idle for a few minutes till idle falls to normal then remove the vacuum line and plug hole on vac line with finger. Check gauge... reset it if you have an adjustable regulator. Must remove the vac line from regulator only and leave the rest of it as it was. factory setting is 39 with vac line off reg.