https://www.youtube.com/watch?v=uaPzcSFCr_E
You may be able to borrow this gauge from Autozone or Oriellys for free.
Line pressure test... run the hose through a hole in your firewall and check pressure while driving. I may do this myself. There is a chart floating around here somewhere to tell you what you should read. I'm still learning so if you already know this and it seems common sense, bare with me.