6L80 tap shift from 2 sources ?/help

[jchidley]

so i have my shrifter tap shift working all fine but my actual shifter has tap shift as well.. now i have heard that you can only tap shift from 1 source because its a resistance signal and adding 2 locations will double the resistance.. but if you were to use an ultra low resistance diode as a 1 way electrical check valve, could you use 2 sources? does anyone know the resistance values the ECM is looking for?

[87skier]

TUTD switch.jpg
This image shows the resistor values and dual switches. Not sure if resistor values are common to all transmissions.