Sounds like a plan.

I may have a camshaft and towers....

If you are interested I will have a look.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

Yes, if you've got a 124 five speed and a manual transmission 240D, you've got it all! My 88 300E five speed just earned it's half million mile badge and is looking a bit ragged, but I still wouldn't turn loose of it unless it was for a nicer one.

As far as the three missing screws go, this might very well have led to the problem. I have some similar experience, albeit on a different but similar engine:

About 25 years ago I was offered a really nice looking '68 230, four speed manual car for super cheap. It ran, but once hot, made little or no oil pressure. Determined to put it on the road, I pulled it apart and started checking. The crankshaft mic'd perfect and the cylinders had very little ridge. I did a valve job, new guides, did rings and bearings an put it back together.

In the process I found the camshaft journals to be trash. MB parts were hard to come by in those days so I poor boyed the cam the best I could and I never got it to hold good oil pressure. It ran great and was a real kick to drive, but I just didn't trust it. If I had it today, I would do whatever it took, but I just didn't have the means at the time.

Anyway, in the course of this disassembly I noticed that the three screws you're talking about were very loose. Once I started trying to conquer the oil pressure problem, I found that there is an oil passage through the head gasket in that area that feeds the cam. I've never really checked on a 616/617 because I've never had oil pressure problems without finding the fault elsewhere, but I believe that if you start looking, you will discover an oil passage there.

All that said, since the bottom is in good shape, I would tend to find a cam and towers and button the head back up properly after making SURE that it has a straight surface. Don't mill it unless ABSOLUTELY necessary, because a diesel just won't tolerate much compression increase, plus the valves and pistons are already quite cozy.

Good luck with it.