Thanks for the suggestions....

I also do not have a test port on the fuel injector rail. Apparently there is an adapter that you can purchase to connect the pressure gauge.

As I have continued to dig into the truck I think mine is an electrical problem. The truck will idle and I can rev it, but when I step on the brake it dies instantly!?!

 

Another update. Took me a while to post this, sorry. The next day I had the same problem so I took out the IAC and replaced it. I wasn't sure it was working correctly and I turned out to be right. It was the culprit all along. Intermittent electronic failures are the WORST. But if you're like me, you can take it out and start the truck. It will start up and rev to somewhere near 2k rpm. Check and make sure it goes back to it's neutral position when you turn the key on. It should always do that and if it doesn't then it may be failing like mine intermittently. Good luck! And pertaining to the last post, have you checked out your brake booster? Make sure it's working correctly?