I made a pop tester and the gauges that you show are MUCH nicer than mine.
They would work fine and you would have a really nice tool when done.

If I had one thing to change on mine though, it would be to find a gauge with a max pressure needle. I have not found one cheap. I'd hold out for a while to try to find one if you have the time.

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The Golden Rule

1984 300SD (bought new, sold it in 1988, bought it back 13 yrs. later)