Years ago I installed 2 of them on my cowl. One for the carb and one for the nitrous. I knew I did not want to drill my hood, so I made a aluminum plate with rubber glued on the bottom to mount them to.
Here's the original car they were on for 20+ years.
I used steel brake line and went down through the cowl vents in the hood.
Transitioned to braided steel flex line to the carb supply inlet in the cowl under the hood on this E body.
Then 20 years later while really driving a lot on the street I noticed too many negative responses. Just the way the cops would look at the car mainly in passing. I got tired of them too, I knew what my fuel pressure was. I have been looking at them for 20 years.
Took them off and it has been much better on the street, not near as many looks from the cops and what feels like is more respect. Plus I take the car out of town on many vacations and did not want it to stand out to the local cops. It helped a lot to blend in more. The car already stands out on it own, don't need racey stuff on the car to be noticed anymore.
Guess what? No holes or marrs on my hood when I took them off.
The lights in them were wired to my running lites, looked cool at night. I custom soldered and shrink wrapped all the wiring and it was done right and for a lifetime. Too bad I took them off!
How I transitioned over to #3 braided hose from steel brake line.
This is the inlet adapter on my gauge to accept steel inverted flare brake line which is skinny enough and would pass thru the slots in my hood. Then I installed the flare nut and double flared it.
South San Francisco and the Pacific ocean with no marks or holes on the hood. Less looks from the cops=win!
