So I pulled a vacuum on it for 3 hours, unhooked everything and let it sit for a couple days. Went out this afternoon, hooked the gauge up (can't connect high side) and it still had the same vacuum reading so I charged it.
When I put it together, I added a 7oz bottle of PAG46. It also had 1oz of some coolant helper and the way I read the bottle, treat it as 7oz. According to the charts, the truck took 36oz of R12 and 7oz of Oil. I added three 12oz can of R134. The can tap had a leak I didn't catch until the first can was half empty, so I may have lost an oz or two. It took much longer for the last can to empty compared to the first two. Low side pressure with AC on high sits right at 45psi stable. Ambient temp is 80deg. Chart says it should be between 40 and 50psi.
In running it for 30min or so, the compressor never kicked off. I pulled the compressor wiring lead to make sure the clutch wasn't stuck and it kicked off immediately and the pressure rose to 85psi. Temp at the vents was about 54deg.
Should the compressor not cycle occasionally?