I've now found a YT video showing exactly the process of upgrading mirrors.....
I didn't even realise the ribbed ones don't even fold back, so modifying the newer ones looks like the way to go.
Thanks for your reply.
I've now sourced a left/passenger side mirror that exactly matches mine so I'll play safe and order that.
The driver's side isn't so bad but I'll play the long game and wait for another correct one to become available...
I have the later version running on my '99 (ribbed miror) car. It came off my 2001 parts car.
I did it a while ago so can't remember precisely.
They do fit and work, but the mounting is different. I believe the 2 rear screws are the same, so...
I've searched online but not found a definitive answer.
I'm looking to replace both broken mirrors on my recently acquired 1998 FL1
Mine look like this:
There are loads of 2nd hand FL1 mirrors on ebay, but not so many with the ribbed...