Speedo overdrive setup

[pedro]

G'day Pete, I was going to pm you this question but I thought maybe other members might need this info too, I've been talking to the sparky and I understand the overdrive problem now, I remember you saying you attached the commodore speedo to the back of the FC one, did you only use part of it?, how did you attach it and how did you continue the cable through to the FC speedo?, I presume the FC speedo will still have to be recalibrated as changing the plastic gears on the box(if it's even possible) would throw out when overdrive kicks in.
                           Pedro

[pedro]

Ok, Pete put me on to Castle auto electrics they do an inline speed sensor for $200 + $60 for an adaptor cable, the bloke reckons you just fit it onto the speedo drive on the box, fit your cable to it then get the sparky to wire it, too easy.
                         Pedro