Good so far with a/c. I just charged the Newport with my propane grill bottle for a test. Not exactly sure how much went in for obvious reasons. Right now it's about 90 degrees outside. A/C is cooling pretty good so far, haven't put a thermometer in the vent yet but it feels good. Roughly 45-50 degrees if I had to guess, which is adequate, so far.
I just charged it to what I thought looked safe based on my knowledge of R134. Still need to look up a proper R12 pressure chart, but I figured I'd post it here to get input first.

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