We're getting some questions about the connectors to the radio control receivers.  The connectors are standard JST connectors (three male pins that fit into a female socket).  However, as these were scavenged from the older system, you may have a JST connector that doesn't fit because there's a small black tab on the side preventing the two from connecting.

Go ahead and take a small utility knife and slice the tab off. Seems we missed a few in our prep.

Now, the new system doesn't use a tab to force proper orientation, so we want to remind you that the signal line coming out of the receiver is the far left pin (farthest away from the edge).  If you're following standard color codes as we suggest, the white wire of the JST cable should be on that far left pin.