An alternative is to cut pieces of heat shrink tubing and shink to a loose fit; i.e., tight enough not to flop off with moderate handling, but not so tight that you struggle with getting 'em off.
I leave a length above the tops so that, after it is shrunk, it can serve as a "handle" to remove/place the caps.
IIRC, I took a spare male Deans, wrapped a layer of masking tape around the exposed male pins, then did the heat shrink bit. I vaguely recall that might have been a little on the loose side; been a while. Hence, my suggestion to not overly shrink the tubing on just the bare pins.
Originally Posted by helicow
You could use unused female deans in a pinch to cover the exposed pins.
Just an idea.