[Elecraft] secondary power connector suggestion?

[Mike McCoy]

Given there are some very creative/imaginative people on this list I thought
I'd ask for some suggestions:

I want to add a secondary power input on the back of my K2 to accomodate a
solar power panel/controller. However, I don't want to modify the back
whatsoever (e.g. enlarge or drill extra holes, etc.). The obvious location
would be to use one of the existing holes for the external xverter.

I don't seem to have any various panel mount connectors lying about and
don't want to go out and buy a bunch of different types just to figure out
what will work since the xverter holes are 'keyed' and thus just any ol
standard connector might not fit.

Anyone have any 'best of breed' solutions?

thanks & 73,
Mike - AD5IU