One is a full size, one is a mid size and 19 years apart. So it is easy decision if you need a big car. 19 years is a loooog time in automotive innovation. If you wrench yourself then SDL is a better car to self maintain. If you farm it out then I would take the CDI. Both cars will cost you dear in any event.

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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.