I'd like to say some nasty kids from the wrong side of town smashed it, but the truth is I caught it on the garage wall. Somehow it compressed and then shattered, and the casing cracked so I need a whole new mirror unit.
I tried the local scrapyard, as they had 2 BX's before, but they have come under new ownership and seem to be baling cars and throwing away all the bits from ones that are "too old" for anyone to want... After claiming they were ordering a BX mirror in and were going to call me when it arrived, then giving me a lot of excuses when I called weeks later to ask if they had it; I decided to go the "proper" way of finding a spare ... the club
