If I read the post correctly, you are $600 into it. Scrap it for $150 and you are then only $450 in the hole. If you are willing to dump $3000 into it then I am sure you can pick up a reasonable shape driveable W123 for the same money. There are just too much uncertainty and unknowns for now. What you see is the tip of the iceberg. I am sure you have made up your mind either ways but you just want affirmation from this forum to back up your decision. Good luck.

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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.