Regarding your cigar lighter, lots of times I have seen people grab this power line and use it for other things since it is convenient and usually switched, so it is likely they used that for the new turn signal system, or some other device in the car. If you don't have an owners manual get one and figure out which fuse goes to the cigar lighter, from removing it and checking what doesn't now work you can trace it down. Also if you have another hot wire with a fused link in it under the dash you can use that if you want, unless you want it back original.
About your temp sensor, if you have auto climate control then you need to have it. If your climate control is manual then there is not need for it. I don't know where they are in those cars, but you really can't see them from the grill on the outside, so I don't know why someone would remove it, kind of strange, remove the cover panel and see if it is there, if not get a new one, unless the connector is missing, which I don't know where that would have gone.
The turn signal deal, I would just get a new assembly. It seems like you may have to replace it all, that would be the simplest method. I don't know if you can buy the individual parts, you could go to a salvage yard and get one, keep in mind that MB uses a lot of the same parts in their cars, so as long as it is the same chasis type, usually you will find the same part inside. Good luck with your project! That sounds like it will be a great car!

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Brian W. Heitman

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