My gosh... I would LOVE a non-Euro 84-85 500SEL! That has always been one of my most favorite Benzes!
If not done though, despite low miles the first thing I would do is change the timing chain guides and rails since it is a V8 and by now they may be brittle with age.
I would love to see pics of this car, so I can dream on.
My 158K 300SEL will have to suffice I guess.