Stop in for a cup of coffee

Well that didn't work well. THere's a cruise going tomorrow. Last time I drove the Swinger the air didn't work. I hooked up the gauges but no pressure. I hooked up the evac pump and when I shut it off it heald 30" of vacuum for about 10 min. I have a leak somewhere. I would like to squirt some die in it but may be another time. It's a Chrysler dealer install set up and i'll be damned, it doesn't have a low side port. High side to the condenser and one on the compressor head. I'm confused how I charged it last time I had the system open for a hose repair. I'm thinking this could be easier with a receiver/dryer with a low side port on it.