From the "they said it couldn't be done" department.
Until a site visitor mentioned it, I didn't realize that I hadn't popped the face off of a 55SH Series II microphone even though I have two. I don't know, maybe I was afraid they would be jinxed.
Based on an feedback email, and research of the Shure knowledgebase, I ordered a replacement cartridge for the 55SH even before cracking one open. When I finally did it, I saw the complex guts of a 55 were replaced by a plastic device holding a fairly standard unidirectional dynamic element.
Yawn.. where were the springs and foam mounts and the oddly shaped classic element? I guess progress has its price. Earlier 55's were not meant for what they are being used for now, so the company chose to be loyal to the physical design, not the underlying electromechanical genius. Then have them manufactured in Mexico.
Curiously, the hole pattern for mounting the plastic device to the back shell of the head is the same as for vintage 55's.
I have obtained the housing for the cartridge from Shure, and will be building Frankenstein #1 shortly.
The R115 sells for $50+ , so it isn't a cheap decision. I bit the bullet for the sake of historical preservation.
That will be the subject of an another article.