The regulator is a 0-100 psi. Buying a little bit better regulator and pump certainly could be a good idea.
The Deutsch style connectors that Danny found are very nice. I started with just a couple of 6 pins for spark but now have 5 connectors (using 25 out of 30 connections plus a couple of spares). You could reduce the number of connectors and make it cleaner. The last time I did this, I used a pick-and-pull 50 pin behemoth and a wiring bundle the size of Marianne's wrist. I went the other way this time because I wanted it simple. Two 12 pins would work. I'm using one port/wire to turn off my AC compressor at idle. I doubt any of you would need that 25th wire.
As an old electronics tech, I personally would rather build using solder and heat shrink with pigtail connectors than to have to crimp a lot of pins to build the connectors. Just my preference.
For wires, I bought a couple of 10 ft long, 11 color 22g automotive wiring bundles $16 each. https://www.ebay.com/itm/22-aw...10-FEET/292158875171