I did all my conversions and it is dirt cheap, less than $70 per car. $20 for receiver drier, $10 or less for the Schrader valves adapters, $12 for ester oil and $25 for R134. You charge it to 3/4 of the R12 weight. I have an extremely good ( science lab grade ) vacuum pump and all the tools. In reality, any good vacuum pump would do. AC is a must for me in SoCal. Rollguy has seen all my cars and he knows the AC works when we went to meets, just doesn't know how cold and comfy it is.

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Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

1 X 2006 CDI
1 x 87 300SDL
1 x 87 300D
1 x 87 300TDT wagon
1 x 83 300D
1 x 84 190D ( 5 sp ) - All R134 converted + keyless entry.