From the Bentley manual diagrams the cruise control for both 86 to 89, and 90+ cruise controls get their speed signal from the spedometer. I just had my cluster out (for another reason) and there is no lug on the spedometer. The 90+ cruise control definitely did not plug into the spedometer when I stripped it out of the donor car(I think it reads directly off the speed sensor). The orange wire on the older type was plugged into instrument cluster on the donor, but I did not look where when I unplugged it. So what gives? I know 89 was a transition year, is it possible my 89 has a spedometer that can only use the 90+ type of cruise?