What position is the Climate control in?
I am stabbing at your problem as I have an '86 300E and so far it seems to run flawless after the water pump change and the idler pulley shock change. I would almost think that the ACC thinks the a/c compressor should be operating if that's where you left the controls before shutting off the engine. I would also image that there is still pressure in the freon line causing the higher RPM while the engine still thinks the compressor is engaged. All in all I think I would fix the initial problem of the compressor screaming at you. Could it be any of the following problems that have contributed to this locking up of your compressor? Has it been serviced lately and they forgot to install oil along with the freon, common cause of lock-up? Is the belt loose or frayed where grip might be the problem? I've also seen compressor head pressures to excessive to restart the compressor as well, generally in hot temps though. I'd also try reconnecting the plug to the a/c with the ACC in econo mode only, to disengage the clutch and bring freon pressure back down to a non-operational level. If all else fails and you just want to make it throught the Winter, then remove the belt that operates the compressor or pull the wire off the freon pressure switch.
"Tell me and I will listen, Teach me and I will learn, Show me and I will accomplish, Involve me and I will succeed."
'84 300SD 256,000 Gold on Brown (Mileage Award)
'86 300E 246,000 Blue on Tan