Well, for reasons I'd like to not elaborate on (my stupidity), I have need to replace a prechamber on my OM603. I successfully removed one on my junk engine, but the one with damaged threads in the current vehicle would not come out and is irreversibly damaged after the attempt.

I need guidance in removing/reinstalling the head, but please bear with me as I go over some background.

First off this is the OM603.971, rod bender, of w140 fame. The engine is using a quart of oil every 1500 miles. Previous owner had run this junkard engine for at least 30,000, but no telling the original mileage.

I'd like to remove the cylinder head in order that that the local Dayton Genuine Auto Parts machine shop might replace the damaged prechamber (part acquired from Metric Motors). Planning to have them do valve seals, etc. (questions to come on that.)

I've got a friend who has done head work on a couple diesel engines (not Mercedes) who is willing to assist if I get stuck in the process. He is not one to skimp and has advised lifters, intake valves, exhaust valves, seals etc. for the head. 12 lifters at $20 a pop is not making my day, but I've seen postings by respected members such as GXSR indicating these do go out of spec. All of this would be done by the machine shop.

The immediate questions pertain to how far to go with valve seals,etc. I want to do an initial part order soon. Here is the potential shopping list:
1. Hylomar sealant – thinking the racing acetone based may not be the best choice, but this is quite confusing, seams like the original only comes from England.
2. Elring head gasket kit – This is OEM. the machine shop says if they plane head some a thicker gasket is needed. I am not seeing that as an option for OM603.971.
3. Canyon Valve guides for both intake and exhaust (1st oversize) – does not say OEM ($5.50 versus $13.50 for Mercedes part on Pelican)
4. Intake and Exhaust valves – Intervalves brand way cheaper than Mercedes part for exhaust valve ($14 versus $58 on Pelican)
5. Valve Cover Gasket – DPH or CRP both 1/3rd the price of merc part on Pelican
6. Cylinder head bolts – about $40 for VictorReinz OEM
7. Cylinder head bolt tool-- need recommendation as Pelican is out. It would be great to find East of Missisippi dealer for fast ship to Ohio. Probably going to call local place here called the Tool Crib so I can get this fast (may cost me $75 that way).
8. Valve Stem Seal set – Elring and CRP at Pelican are $10 or so, merc part $50. My old standby ******** just carries the Elring.
9. Exhaust Seal Ring (Mercedes) from Pelican – looks like one of these going from exhaust manifold to rest of exhaust system (pretty sure manifod will need to come out?)9.
10. Valve Lifters – Ina is supposed to be OEM at $15 a pop which is better than $40.
11. Star Classic W140 repair manual – never seen good info (alldata not great) for the w140. Site is offering the DVD image for $20....Does this sound legit. I heard its not the easiest to use too. (I've gathered some info on tightening and loosening order for head, but don't have any torque specs for any of the related parts...)
12. I don't think kit comes with turbo metal gasket to manifold, the OEM VictorReinz gasket to the drain pipe, or the OEM Elhorn intake airhorn gasket.
13. Valve Springs – well their under valve springs at Pelican and called Valve Keepers. (looks like half a cylinderical shape)
14. Professionally rebuilt injects are ready for installation.

I've concatenated many posts, but this post is dragging on too long for inclusion here.

Stage 1. Tools and directions on how to take apart head
Stage 2. Acquiring parts for valve/head recondition
Stage 3. Pick up parts for reinstalling head

I really need help on stage 1 and 2. Any guidance would be greatly appreciated.

My cautious side (mixed with some cheapskate) says the head does not leak, so remove it and tap the damaged prechamber out with wood dowel and mallet while supporting head (but this could warp head.) If done right, nothing is disturbed and I won't feel like I broke the engine.

This is a huge job so another side says to put in a lot of new parts and have pros do this. More expensive. Downside is if the engine doesn't last or run right with new parts I'll feel like I broke the engine. Less might be more with a long lasting rod bender.

Planning to take a look at pistons and clearances to see if this engine is well on the journey to rod bender status.

The car is in great shape otherwise as I have pillaged many things from the defunct Bambi mobile. Previous owner go hit by the evaporator and many other things. Think I have door lock and bumper work left and it would be darn near perfect.