i finally found a way to get my tach to work with an e6k.i hooked up a wire from the 8th connector on the igniter (not used)to the 2b (yellow/blue)wire on the factory ecu harness.i'm not sure if this is a safe method for the tach,but i've tried everything else and this is the only thing that works,so if your tach blows up,don't get mad at me.btw-the easiest way to get to the igniter is to just remove the cruise control.

 

That is the easiest way to make the tach work. It is what I did and I had no problems over the last few years. It is also what is listed on my site for the stock harness to stock harness connection for the tach.