For my soundhole pickup, I route the wire to the endpin and wrap it around so that it is pinched between the strap and the guitar body. Tension/slack can easily be adjusted so the wire doesn't drape unnecessarily nor pull on the pickup. From there it can be dropped to the floor, routed through your trousers belt, whatever suits.

I don't understand the suggestion to use an endpin jack. The ones I've seen require enlarging the endpin hole with a drill, which is absolutely a modification (you can't go back to a standard-sized endpin), and the OP explicitly stated he did NOT want to do any modification. Furthermore, to my knowledge each pickup would have to be wired to said jack, which means removing the strings and working through the soundhole to make the connection. Doesn't sound simple at all - am I missing something here?