Hey, I just put a tether on mine! It was dead simple really, I just drilled the hole next to the key, and there's a plug with a ground wire and the line that goes to the kill switch right there. Look for a two-pole plug with brown and black wires. I bought my tether from SLP; it does come with a generic connector, but I pulled the two spades out and put them into the existing plug. Works great so far! Keep in mind, this is on an '02 600, but I'm guessing an '03 800 would be the same.