I've changed my 4.56 gears to 4.11's in my Trooper II Turbo Diesel and now I need to get the speedometer squared away. I've heard of a mechanical in-line calibrator (made by Borg Warner?), but I can't find anyone who sells one or even list's one. Does anyone know where to find one or another product similar??? Any other ways to fix the problem??? Many thanks.

Thanks, Dana
2 - 1986 Trooper II C223T's
1 - 1981 Isuzu I-Mark (2 door coupe) 1.8 diesel