As long as you let the engine rise to operating temperature and the oil cap still stayed still you might do okay. Remember the coupes have coupe specific parts like the rear window regulators. You might sell enough off to get the engine free. My kind of preffered deal.
If the rear quarters are unrusted in that climate they too might sell well even on ebay. The shipping might be a bit but they are not available aftermarket I believe. Expensive as well from mercedes. Coupe doors with no rust might be a hot iitem as well.
The coupes are developing a following of sorts it seems with time.
Rough and smokey for a minute or so is normal in my experience with a diesel that has sat quite awhile. The second start will probably be cleaner. Sounds pretty good.