Hi Ash (& welcome of course).Hi Steve,
Most interested in your z3 wing mirror fix, might like to take you up on your repair offer as have just experienced exactly the same problem.
Didn't quite understand the procedure though, would be interested to know how it would work, maybe you could let me know, I assume I would need to send you my corroded wing mirror?
Regards Ash
It doesn't look like @Woodsta888 has been around for a while, so I'm not sure the offer will still be available!
There are various fixes for wing mirrors including some chap abroad who manufactures new wing mirror parts in better materials. These 2 threads may be useful -
https://zroadster.org/threads/bmw-z3-door-mirror-fix.5083/
https://zroadster.org/threads/at-last-a-cheap-easy-fix-for-broken-bmw-z3-door-mirrors.4901/
Hope that helps you out some, if not just let me know!
Gary