Have been paying attention to some of you having problems with various aftermarket tachs working with stock harness. I am having Westach build me one to work with it. First attempt will be with submitted info from service manual and a previous post that listed 100Hz @ 3000 rpm. This made sense to them and they said I should see it in 3 to 4 weeks. If we don't get it right I'll drive up there after that and we'll work out the kinks. They are only a couple of hours away from me and make really nice guages. Will not quit until we have it!