When I've needed to check fuel pressure at wot on the road, I just tape a small mechanical gauge to the windshield right where I can easily see it.

Although there was talk of a go-pro....... So I guess the gauge could be anywhere the camera could get a good look at it.

68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123
Dealer for Comp Cams/Indy Heads