I just re-installed the AC in my Toyota. Been without for too many years.
To do the conversion RIGHT. You need some extra tools too
Parts
1. R134a (2 cans should be enough, get the big cans that have the oil already in them)
2. Conversion fittings ~$10 max (there are different sizes and styles, Got mine at Napa, the ones that came in the retro kit didn't work)
3. New Reciever/Dryer - (paid $20 at Napa)
4. O ring kit (can't remember price) Try Napa
5. Conversion oil if keeping old compressor
6. AC system flush $10 (Optional but a good idea, I did this)
Tools
1. Air Compressor
2. Vacuum pump
3. R134a manifold gauge set
4. Blow gun
5. Shrader valve tool (not necessary but helps) the old pressure fitting use shrader valves and the new fittings from Napa have new valves built in.
I bought my reman Compressor off ebay for $80
I did my whole truck with a new reman compressor for $200. That includes the gauges and the pump. I already had a compressor.
All the conversion kits include are freon and the fittings.
This is a link for the procedure. Its on a Ford Ranger board, but the process is the same. Just disregard the orifice tube thing, you dont have one. I also didn't do the clutch cycle switch thing that he did. Other than that I followed the procedure and my AC is ice cold.
http://www.rangerpowersports.com/forum/showthread.php?s=&threadid=128279&highlight=R134a