If you don’t use a key at all (i.e. you want a phone only µBITx) then this hint from Doug AC9RZ might be useful.
Doug folded over about 5mm of the bottom of each leg of the 4.7k resistor to bulk them up. Then he crimped on molex kk terminals on each leg. He put heat shrink on each leg and then popped the resistor in the digital connector where the wires for pins 2 and 3 previously resided. After double checking with his DVM, the rig was fired up and all was good.
Justin N2TOH suggested that just tack soldering the resistor to the back of the connector was easier, so the wires could be completely removed from the harness.