I bought the Haynes tech book, a good set of gauges, pump for evacuating, and a few other simple tools. You can read the book cover-to-cover in two evenings. After that I have done all my own a/c work and all my cars blow cold. Even my old 911 is cool and the a/c in it was never great. Compaired to some of the mechanic work guys on this forum do regularly a/c is a breeze

Just my 2 cents

 

Im replacing the A/C Compressor..............the seals go bad if they dont get enough use

 

Sounds like you are on a roll and have the tools and equipment to get it done.As for the condenser cleaning , just make certain the cleaner is not too caustic either way acidic or base and rinse the heck out of it to make sure it is neutralized. A reverse low pressure blast with compressed air and a wand or solvent gun (piece of 1/4" or 5/16" copper tube w/ 90 deg.bend) will sneek right down between the rad. and cond. and blow the stuff out lodged in the fins.Take care not to use too much pressure or contact the fins, they flatten/bend quite easy,then do your wet washing using the same wand w/water. Another item I find usefull is a long handled brush to assist removing heavily impaled what nots on the front side of the condenser.Tip: use some gloves or have lotsa band aids handy.
I use a 30# cylinder of refrigerant.With your 2 -14oz. cans suggest you dump one in upside down into high side while system is in vac.Then start up and add the second can upright as a gas into suction and monitor temp/press with your gage manifold and a touch of the suction line.It should start to get cold as you near full charge and as I'am sure you have read in other posts the cold will also follow across the air registers from pass. side first to driver side as the evap. finally gets happy with a full load. I did a comp. change not long ago and read around 35# suction & 230 -50# head with the exact factory label charge using a calibrated charging cylinder. This was during a triple digit day here in Calif.
Here is hoping you find a nice clean screen on the tube and good luck with it.

 

Tackled the job on Sat. Replaced expansion orfice (the GM S M says carefully use a pair of needle nose pliers to remove the orfice) I had to use thin VISE GRIPS and the orfice wanted to stop about half way out of the tube. It was missing its O-ring. Fashioned several hooks to go in blind and try to capture the missing O-ring...NO LUCK. New orfice went it to its O-ring and felt TIGHT. Took it out and dipped it into a bottle of GM refrigerant oil and it slid in just like a slipery eel.

Replaced both valve cores large and small ones. Evacuated system down to about -28 in of hg for at least a half hr. Sucked about 3 or 4 oz of oil into system as the old orfice tube was bone dry. Re-evacuated system and then charged it. It took almost the whole first can first in the high side than in both sides. Used a bucked of HOT water to put the can in and warm it up so more freon would go in. Finally closed high side and started the car and A/C. Sucked the rest of the can in to the low side and did the same with a second can.

Results: GM Manual says in 90 or 100 degree ambient temp with about 70 or 80 % humidiy engine running at 1000 RPM the high pressure should be about 245# and the low side about 28# with interior temp on recirculate at abt 38 degrees or so at center dash outlet. I had to interpolate as it was really about 95 degrees ambient air temp. My readings were about 275# pressure hi side and about 38 to 40# on the low side with the temp at center air duct using an AC thermometer in recirc only about 60 degrees F. Did drop from outside temp but even at 2000 RPM only went to 55 degrees at center outlet. The system is on the the troubleshooting CHART C and the suggestions inclued air in system (NOPE) under or over charge (NOPE). Don't know why it won't cool better. Maybe compressor has seen better days but I'm not in the mood to disect the cooling system (must take off water pump to get the compressor off). I really thought replacing the orfice tube, evacuating and recharging wou do the trick. Getting cooling but not enough. BIGHANK