Pull the plug off of the seat switch and take a piece if insulated copper wire, bend it in a U shape, and insert it into each "connector blade" (don't know how else to explain it) on the plug. One can also get spade terminals and crimp it onto the U shaped wire and push the spades into the plug. Then take some electrical tape and wrap the whole thing so it doesn't come apart.
LEGAL DISCLAIMER: I saw this on another website and are just passing the info along. I DO NOT do this myself.