Fuel pressure hood mounted gauge

I have that set up, though I didn't buy it from Gbody.

I wouldn't get it. The mount sucks. After a few years it is weak at the bend and the gauge keeps falling out (forward).

If you are only going to put it on for testing, just get a gauge and line and duct tape it to your windshield. Might not look great, but after all, definitely not permanent if it is for testing and you might as well save the money.
TRCustoms has a nice unit, well done. They are a little pricey, but you get what you pay for. Mark used to offer a twin unit, which I like a lot, but I couldn't afford them at the time and he has since stopped producing the mount.
http://buickgn.com/fuelpressuregaugekit.htm Complete kit, doesn't get any better than this. :)

I have the TR Customs setup on mine. Looks nice, and I like being able to see the FP while driving. If you get tired of looking at it, just unscrew the bracket and mount it under the hood on the fender well.