Source for very small connectors?

I'm finally moving a project to assemble an approximation of the C&O #6500 A/B/C TR-3 "herd" out of an Athearn SW-7 cow and 2 calves off my to-do shelf and onto my workbench. There are good notes on making a two-unit TR-4 in the December 1997 C&O Historical Magazine, and I'm extrapolating from there. I plan to have the units drawbar connected, with Athearn power chassis in the two end units and provision for a DCC decoder (maybe some day with sound) in the center dummy unit. To facilitate servicing the units, I'd like to use two very small 6-pin (2 for rail pickup, 2 for the motors, and 2 for the end headlights) plug and socket connectors between the center unit and the end units. The connectors can be hidden up inside the center unit, but should be easy to disconnect when I pop the shell off. Any suggestions? Geezer