DIY's, other interesting documents & links
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Interesting links

Z3 related links
 
International forums about Z3
Spanish Z3 forum: Bmwfaq.com
French Z3/Z4 forum: Z3club.fr
American Z3/Z4 forum : Bimmerforums.com
German Z3 forum: z3-roadster-forum.de
German Z forum: zroadster.com

Z3 Coupe specific
Intesting website compiling all current M coupe for sale in the USA: Mcoupebuyersguide
The great Coupé Cartel: Coupe Cartel

Other interesting websites
Z3 accessories, focusing on leather parts: LeatherZ
Website to identify the extras of your car BMW VIN Decoder