Attaching Potentiometers to VEX

[billbo911]

I've looked and searched, but I haven't found these questions asked or answered, so here they are.

The Vex kits use square drive shafts and holes to drive gears and wheels. I need to attach pots for position feedback, but can't seem to find any simple way to do it. I figure either coupling adapters with round holes for the pot on one end and square holes on the other to accommodate the axle. Or, round on one end and a square post/peg on the other to attach directly to a gear.
What I would love to hear is that this has already been solved. If not, that at least someone has a suggestion as to how to solve this simple issue.

The next minor issue: All inputs and outputs on the Micro Controller require male pins in their plugs. I have seen several sites that I can purchase female pins and plug sets and wire in bulk. These have all been R/C Hobby sites. What I have not seen, although my searching has not been all that extensive, are male pin and plug sets, let alone ones with keys, like the plugs in the VEX kit.
Again, I'm open to suggestions.