I try not to use vampire taps unless I have to since I have had flakey results with small wires. You're probably best off with the smaller, red ones, though. Carefully try one on a Kenwood wire. Even if the jacket is a lot thicker, I can't imagine the conductor is much bigger than 16-18G (I could be wrong!). Red taps are for 18-20G, I think, and IIRC the Empeg sled wires that you care about are between 18-22G. If you use the blues (made for 14-16G) you'll wind up with a poor connection if any to the Empeg wires.