You haven't mentioned what you want to use the car for? If your end game is to drive I would let it go. Project cars don't always have to be about money but for me it is a factor. Plus this car has just been sitting too long...and outside.

As mentioned by another here, those sedans are not worth much so your time would be better spent on a more desirable model. Besides the obvious reasons for this comment, another is that projects often times don't get finished and this car would be very hard to "off" in the middle of its resurrection.

If you want a car to drive, get one running. Someone I know just picked up a 1991 300 SE for $2100. One owner, 135k miles, original paint, champagne color, leather, only big issue with it is the AC doesn't work. Garaged, so the paint and interior is an 8/10. My point is there are better cars out there for less than it would cost just to get this car to run and stop.