here my collection of all the important things
http://www.bimmerboard.com/forums/posts/632842
DK stands for German Drosselklappe
http://www.7-forum.com/modelle/e32/drosselklappe/

http://www.fibersonde.com/e31/pdfs/DK1.jpg

brushes
if you find 4x5x12mm that should be good to fit or make to fit
http://i71.photobucket.com/albums/i1...0_1634_410.jpg
http://i71.photobucket.com/albums/i1...0_1640_130.jpg
http://i71.photobucket.com/albums/i1...0_1638_710.jpg
http://i71.photobucket.com/albums/i1...0_1637_180.jpg