Not sure about adding oil to the drier. If you are evacuating the system you need to add oil for sure. I heard 6 oz oil is total capacity. Any PAG 100 oil is OK. You need an A/C line spring disconnect tool to remove the line that goes to the evaporator. These are tricky to use. You need to expand a spring inside the joint until it can pass over the flared end of the pipe. You must use the tool, don't improvise. Sets are on ebay all the time. Do a google search on OTC 6517 or 6538 to view the tool. There are two O-rings on this connection. There is an O-ring on the end of the rubber line from the compressor. Mine was impossible to remove. I had to disconnect it at the compressor end, the 6mm allen bolt, then off the car on the floor used a 5lb mallet to whack the wrench on the hose fitting part (after soaking in PB Blaster for a day). I hit it at least 10 times before it came free. The threads were seized. Use a wrench to securely hold the fitting welded to the top of the can when you do this. Be careful, it is very soft metal. If you need to do this perhaps you should also buy the O-ring on the compressor side, it is a weird size. Don't leave the can open very long, the dessicant will quickly absorb moisture. I removed the headlight and hood release latch to gain more room. I removed the old one by removing the two 10mm bolts that secure the black lower splash shield. Then removed it from the bottom. Not sure about your gauges, vacuum is read in inches Hg. Other side may read PSI. I would not tighten the band on the bracket until you get the connections complete, you may need to orient the bottle somewhat to line up the evaporator line. Misalignment here will make it impossible to push the line into the end of the drier tube.