Looking at a '75 300d with "low compression"
 

I haven't seen it yet in person but it looks really good in the pictures. Just been in storage seven years and won't start. I like the OM 617 in the W115 body, and it's red.
I have two questions;
First, the car doesn't look like it's got enough miles on it to need a ring job. I think the problem lies elsewhere. Maybe the fuel pump isn't holding up to the new fuel? Any ideas?
Second, assuming the worst, and it's really dead, what would I look for in a replacement engine? Bolt in compatability is nice, but I might be willing to do a little more work for a turbo or something. I guess I just want it to fit the tranny and the engine mounts and not get to radical. Anything I should specifically avoid? Would a 6 fit?

I just read on another forum that the "California edition" turbos mount a little higher and are easier to fit into a w115. Anyone know anything about that?

Hmm. That's good to know. Thanks for the pictures! I've been trying to visualize various verbal descriptions.
I've been thinking that the rest of the car looks good enough that I might get it and worry about the engine later, but it sounds like I should look a little more closely at the engine.

BTW, why is this starter special? Is there narrow clearance between the engine and the frame or is it a tranny or flywheel casting type of thing?