+1 Ron's got right formula to finding your solution. If you leave the kill switch engaged and there's a electrical "leak" in the ignition switch at the off position (through fuse #2) you could gradually drain the battery flat. Your meter readings indicate a good regulator so that's a bonus.

A positive attitude may not solve all your problems, but it will annoy enough people to make it worth the effort. Herm Albright (1876 - 1944)