I had a hard starting issue on my 97 850 GLT with 115K when I checked the spark plugs #5 was oil fouled and oil was sitting on top of the cylinder. All the other plugs were perfectly fine. I have pulled the head and brought it to the machine shop, not being that knowledgeable of what could be wrong I knew I would need to have the head checked anyway. The head turned out to be in perfect condition so I had left it to the machinist (who has been in business for over 40 years) to do what needed to be done to it. He cleaned it up, new seals and skimmed the surface a bit. He suggested that my problem was most likely bad rings on #5 cylinder and that I drop the oil pan and push #5 cylinder out and replace the rings. anybody have any thoughts on this or had a similar experience.

 

People often mistake fuel soaked plugs for being oil fouled. Sorry to read that you pulled the head for that. I would do a simple compression test to see what compression is before going over board. Maybe you can have the car towed to a shop that can check the block before putting it all back together. I'd rather pay for 2 tows and have the bottom checked than to put it all back together and learn that something is wrong.

 

Yes it is unfortunate that you did not do a pre stripdown compression test before removing the cylinder head.
At only 115k miles the readings should still have been quite good.

By replacing the rings in #5 cylinder alone you could finish up with the other 4 cylinders having a lower compression than normal discrepancy tolerances by nature of them not having had new rings also.
I would follow rspi's suggestion to cofirm a favourable overall condition of the block and the existing piston rings prior to reinstalling the head.
It gives you 'piece of mind' then.