I was planning to re route the wires through the ROPS in the spring and I will cover the connectors etc. But I'm intrigued about the 10amps through the ignition. What will I ruin by doing that?
The switch may be rated to take that much amperage, or more, but it would be better to wire the lamps on their own dedicated circuit. There may be wires going back there, but I would check out the wiring diagram to see exactly how Mr Kioti ran them. You do have the option to leave it as is of course, and it will likely be OK.
There isn't any tractor wiring "code" I'm aware of, so I tend to fall back on my marine wiring ethic for outdoor power equipment since it tends to get more abuse than regular automotive. With this in mind, I like to keep high amp draws separate from existing circuits. I would see if there is an open fuse hole on the panel. Fit it with a 15 amp fuse. Run wire to the line terminal of your solenoid, and the load side to your lights. The switched power hot comes from a toggle switch you put somewhere convenient, and is a very low draw so it can be a hot tap from the light switch or your IGN ON. On my boat I would just run the whole thing thru a 15 amp circuit breaker.
I use marine grade tinned wire, adhesive lined heat shrink crimp ring terminals, and tinned bus bars from genuinedealz.com. They'll have the split loom too, or you can use the 14/2 duplex marine grade wire they sell. Good stuff. They also have battery cabling, terminal boots and supplies to upgrade the (junk) that came from the factory.
Can you help me understand how exactly the damage is done. I made an error I guess of assuming since the pigtail was located such to run a rear facing light, it would be OK to use it.
Don't know whether Mr Kioti thought to use one small 10 watt lamp or two 55 watt or what, so don't know what the circuit can take. Damage will be to the wire as in meltdown or fire ( Ohm's Law...resistance equals heat). The device (lamps) may not fail before the wire does, so that's why we need circuit protection. Assume nothing.
If you drill your holes in the center of the bar it will not diminish the strength in the least. Protect the holes with the properly sized rubber grommet to avoid chafe.