I've did a search, and could only find T-56 and aftermarket speedo questions.
I just had 3.73s installed not to long ago and need to recalibrate the signal.
Here's how I've tried hooking it up-please let me know if this is totally incorrect. I spliced into the "A10" brown wire comming off of the ECM to pick up the VSS signal.

12v source------------to--DD PWR terminal
ground-----------------to--DD GND terminal
VSS signal-------------to--DD Sig IN
Out 1/Out 2-----------to--ECM

I'm using the application #2 chart.
My speedo reads the same as before I tried using the box, and I've played with the calibration table settings as well.
Any help would be appreciated. Thank you, Roy

 

anyone????

 

I had the same problems. I would have to go look, but I think I ended up using different outs.

Jim Buckingham