I did some tests according to your A-7 charts this afternoon and this is what I discovered.
I got a 7psi reading with the motor dead cold and the fuel pumped unprimed for about a week. I turned the key and got 57psi and it dropped to 52psi after 60 seconds.
With the supply line pinched, I got 56psi that bled down to 51psi after 60 seconds.
With the return line pinched, I got 59psi, which bled down to 55psi after 60 seconds.

 

On this picture, you can see I decided to go with the "above 47psi" option for giggles. I get random readings every time I prime the pump, but it's almost always above 47psi.
If I turn to page 2 of 2, it says to disconnect the return line and put it in a container. If the pressure stays above 47psi, to check for a blockage between the disconneced line and the regulator. If the line's okay, then the regulator's bad.
If the pressure falls to between 40.5 and 47psi, to look for a blockage in the return line to the tank.

I guess tomorrow when I've got the plenum off to check for leaking injectors, I'll throw in a new pressure diaphragm and run the test that calls for unhooking the return line.

Kind of looking like the pump might not be the culprit after all.

 

Have you got it to crank and run yet?

 

Yeah, but it only stays running for about 30 seconds then bogs out and dies.

 

Has it slowly started doing this or was it all of the sudden ___? Check to make sure you have no fuel line leaks. Try to get the pump to run for a while then off and repeat for a few times, then pull a spark plug that has an open valve and see if it is wet. If you are into tuning try to run a datalog of when you can get it to run. Maybe try to use a stethoscope and listen to the pump while the engine is running to hear if maybe it (the pump) can not hold pressure.

 

It all started when I did my heads/cam swap. It ran fine and dandy for about three weeks after, then all of a sudden, this started.

 

Well, nevermind.
This morning I took the plenum and runners off so I could lift the fuel rail.
I installed a new pressure regulator diaphragm, the old one was fubared and looked a little too brittle. Why not buy a new one?
I supported the fuel rail with some wood blocks and ran through the A-7 tests again. I decided to let the car sit for a few minutes and do them again. This time, I turned the key, checked the pressure and it was holding at 46psi and very slowly bled down to 43psi. I decided to turn the key off and when I did, I heard a pop. When I looked under the hood, something had splattered all over the radiator shroud. Come to discover, the #1 injector had blown clean off the fuel rail!
In the past, when I shut the car off, I had been hearing something that sounded like a pressure release, but couldn't ever find out what it was. I can't really smell gas unless there's a high concentration of it, so I never could put two and two together because one of the two's was always missing. When I took the passenger side plenum off, I found a little gas on the intake base under the #2 injector, but the injector itself was dry. I'm assuming it would have blown too.
I'm heading over to Autozone right now to get some new o-rings and whatnot and will be taking the fuel rail off this afternoon.

Oh boy...

 

While you are at it, buy some of those lock rings to hold the injectors in the rails. I know a lot of people don't bother using then, but they do have their uses.

 

Already got them on there.
I put new o-rings on them all, blasted them with brake claner and wiped them clean and reinstalled them all. Primed the fuel pump a few times and the pressure sat at 46psi and bled really, really slowly down to about 43psi before I shut the key off. After that, it continued to bleed down to 35psi, which your chart says is okay. Not one of the injectors is leaking. The rail's already reinstalled and I'll be tackling the runners and plenum in the morning.
Apparently, it did need a new regulator, but it was only part of the problem. I could see where the injectors had been spraying fuel out the top o-rings onto the injectors themselves. Dirt had gummed up around the injectors where it meets the rail.

Tomorrow I shall start her up. Cross your fingers dude!