I found an easy fix last night and posted it on this attached thread. I also determined the problem to be the worn plastic bushings and the slop they allow, but this was an easier "work around" the problem and my ACDC is now working perfectly:

http://pinside.com/pinball/forum/topic/tech-help-please-acdc-autofire-plunger-getting-weaker-and-weaker#post-1336664

Until someone can come up with an easier solution...yes! At least it is now working properly with a minimum of effort to make it work. When the velcro gets worn thin I will use two sided tape on a metal shim to preload that sloppy linkage. We obviously are not getting any valid repair suggestions from Stern on the problem.

I would bet that there is a standard sized oilite brass/bronze bushing that would work exactly like RacerRik's custom made part. When I worked in special machine design we had catalogs from every manufacturer with their standard sizes. Maybe we have someone out here in the pinball world who has access to that information? RacerRik listed the nomimal sizes that would be needed. Worst case scenario is that we might have to file 1/16 off the overall length of a standard piece to make it work.

I've been looking online for the past hour and all the manufacturers for flanged oilite bushings seem to be in the UK! I will go to a well stocked machine parts supply place I know of in Detroit after the holidays and see what they have. I'm pretty sure those crummy plastic split sleeves need to be replaced with a sintered bronze bushing in standard dimensions.