IRD said:
Just reading your post again. To clarify can you replace each individual switch top or do you need to replace all the tops together? Hence your comment about what switches I have.
Supposedly you can do the tops individually...see this post, which is in the other post I mentioned above...
https://z4-forum.com/forum/viewtopic.php?f=23&t=110358
I do have a full unit that could be sacrificed but seems a shame for a fully working unit to be dismantled that way!
let me know if you're interested in buying it after reading the link and I can send you a better picture (this was before I removed it) !