I don't see how it would be all that difficult to swap the HVAC system from a 300D to a 240D. I have had the dash out of my 300D twice, once to replace the vacuum solenoids and the other time to replace the heater core. To do the heater core the whole HVAC box had to come out. Time consuming and tedious, yes. Difficult, not too bad. If I had a 240D sitting in the next garage bay to swap the parts directly over it would be pretty simple.

Granted this is pretty involved and you have to have the tools, space, parts car, time and ability to pull it off. Its a lot of effort but the result is a much simpler HVAC system and likely years of trouble free operation. I came very close to doing just this when I had to go in the second time to do the heater core. I just couldn't find a 240 donor fast enough. RT

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84' Mercedes Benz 300D Anthracite/black, 171K
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