I have an 01 SVS and fitted heated grips, I took the switched live from an orange (with yellow trace) wire just below the fuze box (under seat), it is nice and convenient to hack into there and being the fan feed wire, doesn’t ordinarily need to carry much/any load, ideal. You will need some bullet joints/crimps or at least a soldering iron and heatshrink to make a neat job of the join. The –ve you can just wire direct to the battery.
I don’t have a wiring diagram for a K5, but probably the same colour scheme? If you can find an online diagram I would be happy to take a look and suggest possible ‘tap’ points.
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