Long list,

Evaporator, does not have to be replaced, the R134 is supposed to have a larger capacity and cool better. Same thing applies to the condenser coils by the way.

O Ring kits will have lots of extra o rings, you can take everything apart and go down to a parts store and buy the sizes you need. The ScanTech kit is actually pretty decent, you will end up with several sizes left over.

Expansion Valves are cheap, not hard to replace, and that is one of those things you really need to do. There is an R134 expansion Valve and that is one of the the four things you should really do to make this successful. This is the same one used in Saab's and Porsche's by the way.

Dryer has to be replaced, goes on last, and is not expensive. Be sure to use new o rings. After market will work just fine if the fittings are all the same.

PAG 40, if you are going to open up the system, drain the compressor, replace the expansion valve, you are cleaning the lines away from being able to use it. If you open the system up that far and don't use a cleaner on the lines, you may wish you had. Key here is to remove the compressor lines and aim them at the ground. Remove the dryer and aim those lines down, and last but not least remove the expansion valve. You use the two lines inside the car to spray in the cleaner and then use plenty of compressed air to blow the gunk and junk out of the lines. The only line outside you need to clean with the system open is the line from the compressor through the evaporator to the dryer.

Fittings get new O Rings and use mineral oil to lube them up. The R134 fittings screw into the compressor, the low side on my 86 model is a PITA to reach since it is so close the frame rail. Going to put a 90 degree adapter in to make this easier to reach soon. You install new oil (Pag or Mineral don't mix them) minus 1 Oz for the dryer and after replacing the o rings install the lines back on the compressor. Install the Expansion Valve next use mineral oil on the new o rings. Install the low pressure switch on the dryer, add 1 oz of oil, lube up the new o rings and get the system sealed up so your dryer does not suck up all that moisture.

As far as pulling the vacuum, you can "Borrow" a compressor with the hoses and fittings from one of the Chain Parts house. You will want to have a set of gauges most likely. Harbor Freight has a decent set for less than $50 most of the time.

Lots of work but the resulting cool is really worth it.

Regards,

Paul