not an a body but need some help

I'd bet fuel. Inspect the line, REAR to front, look for kinked, line, rubber or steel, and collapsing rubber connector lines. If you have dual tanks, suspect the valve.

Invest in a vaccum/ pressure gauge, 20 bucks at any store. The pump should pull 12" or more on the suction side of the pump, and you can use the gauge to read pressure

"Read it while driving?" Sure you can. String the hose up out of the hook, through the grill, whatever it takes. Tie a rag around it and use wire tie wraps to anchor it to the cowl grille or even a wiper blade. After all, you're not gonna GO cross country are ya?

Tank venting? Pull the cap off for a test run