I have a 1988 560 SEL with about 207,000 miles on it!

The engine is strong and quiet, but, burns oil and smokes after long drives and when I start it up after it has sat for a few days.

Clearly it seems I need valve seals and may be more ....

I read about the Auto Rx on the site - it seems like a reasonable experiment ....

But, what I would truly like to know is -

Should I replace the entire engine once and for all? I intend to keep this baby for a long time. If so, what and where are my best options. I see sites that have engines from $2500 to $9000 (low miles)!! Truthfully, if I were to replace the engine, I would love to put an AMG version in there - but, don't know what to ask for and where I can get it and cost it. Would like to get the entire AMG engine and headers and exhaust.

The other is - replace the top - head and the valves etc .... now, I think (and I need your help) I can do this myself .... am a level B DIY'er ..... would this cure the ills and keep me going for a long time?

Am not sure what condition the pistons and rings are in. But, when I have the head off, I can change the rings too right?

The front seems soft, I did change the shocks recently and I am led to belive that I need new spring/coil as well ..... would a soft front end with understeer be due to coils? It drifts a bit, but I did change the steering shock and the car is aligned.

THe last question should be easy - there are so many squeaks and plastic groans - I have put conditioner on the seats and door, but, I still can't get these noises stopped. It feels less solid due to the noise alone! Any suggestions? I have tightened, where possible, all the screws and the like ..... still creaks and chirps inside.

Thanks for all your insight ...... the car is doing well. I put a lot of time into it ........

K