I tried to install the pins/wires from the 3pin connector into the Duratrax 5 pin connector but they would not fit. The holes are too small for the pin to insert all the way.
I may end up cutting the standard plug/wire set and solder it to the other wires I have installed on the battery side. I will be stopping at a couple hobby shops this week when I'm out of town and will look for the proper harness there.