I have kept some pictures of a W55 short shifter because i thought one day i would try making my own, i recon the spacer/extension looks about 20- 25mm or so. The pictures are quite small and poor quality but if u want i can email u them.
by the way are you making any to sell. could be keen.
Thanks for the reply mate. Those pictures would be great if I could have a look at them. alankidd AT post DOT com. Yeah a guy on toymods used 20mm and he think that does the trick. Probably will just knock one up for myself and not for sale.