If it were my airplane, I'd try to avoid breaking the wire bundle at the wing roots.
I'm flying rental machines that are 40+ years old that have never had the wings
off! Unless you KNOW that routine opening of a wire bundle is a good
thing to do (perhaps your airplane folds the wings and goes onto a trailer
between flights) then I'll suggest that you assemble the wings with long pigtails
of wire extending out the roots. Wire them into the ship's systems solid but
put about 6" of slack in the bundles at the roots. When and if you need to open
the bundles, go ahead and cut them. When the wings go back on, restore the bundles
with butt-splices. The slack wire at the roots will let you pull and replace
the wings perhaps 5-6 times by cutting out the butt splices before you need to
do anything like extend the wires.
If you really gotta have wing-root disconnection of ship's wiring, consider
the technique below:
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