Splicing A Heated Jacket….

So I bought a few years ago a basic Gerbing jacket which is such a godsend. Thinking at the time the simplest one (no power take offs) will do…. Now a few years down the line I’ve bought some Keis heated gloves and they have their own wires (and batteries).
Has anyone added (as in spliced) to the Gerbing system so it can run add ons and how did they manage it without too much clothing damage?