BMW cambelt change - when and Up-down headlights!

[John Smith <john@xxxxxxxxxxxxxxxx>]

If there's a digester out there who know the *official* BMW
recommended time to change the engine timing belt
for an E30? Could you please tell the digest? (Please not email
as maybe some follow-up comments will arise). I also be interested
to learn of about any belts that have actually failed in service. (Email
is fine for that - no names published but just times/mileage etc).
(john@domain.elided)

I'd like to add this info. to my belt-change description
at http://www.jssm.demon.co.uk (now under BMW link)

Unrelated, but would like to know how the headlight
up/down adjusting mechanism works (325i '89)? There is an
illuminated adjustment control located just 
below the main headlight switch. Two plastic
tubes go from this control to ... somewhere.
It used to work fine but now turning the adjuster
has no effect on the lights headlights position.

Thank you.

- -John

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