I did that job on my old '86 190E 2.3. No fun. Jack the car up high and use good jackstands. You will have to loosen a few things to get it out. Don't forget the fuel cooler circuit. Release the presure and cap the lines while they are disconnected. Seems I had to raise the engine slightly. I had to replace the compressor too, so while I had everything out of the way, I replaced the motor mount. To finally get the line in or out, you have to kinda screw it into position. Twisting it in from the top as I recall. Suddenly it all falls into place. Plug the ports in the compressor when you take the main fitting off and oil loss will be minimal. Cap/plug the hoses and all fittings if you are not going to replace the dryer. Want to keep exposure to moisture to a minimum. I converted to 134A when I did the job and also replaced the TXV and receiver/dryer. Cools well, but that darn 134a will find some place to slowly leak out. I replaced just about every O-ring and it still needs to be topped up each season. May be leaking thru the hoses themselves since they are not barrier hose.