On the subject of switches for aux lights:
Rather than find and buy waterproof switches, and a good place to mount them, and then drill holes in a perfectly good tractor (not that I'm really against doing so...), I used the factory light switches. It's already in a good location, it's waterproof, and now I have a single switch that turns on the factory headlights as well as the two aux lights on the ROPS. While I was at it, I wired the factory hazard switch to turn on the strobe light on the ROPS.
I tapped into the factory switch and installed a relay to do the actual switching, so I'm not loading the factory switches any more than they already were. The load wire to the relays comes from the battery (which on the BX is within inches of the factory switches under the "dash"), through a fuse, and to the relay. I then ran new wires under the tractor in wiring loom, up the ROPS and to the lights. The lights (one forward, one back, and a strobe) are installed on a piece of angle iron that is attached to the top of the ROPS with two hose clamps.
I used a 4-wire trailer wiring harness for the wire from the relays to the lights. The plug is positioned on top of the ROPS. This allows me to easily unplug the whole light bar assembly, should the need/desire arise. Since trailer wiring harnesses have 3 "hot" wires in them, I used one wire for each of the two lights (attached to the same relay), and the other wire for the strobe. The ground wire is attached to the tractor frame at the bottom of the ROPS. The ground wire is carrying the full amperage of the other three wires combined, but it's not as long, so that shouldn't be as big of a problem.
The only potential downside to using the factory light switches is you must have all or none in terms of which lights are turned on. As was mentioned somewhere on this thread, I've found that for many uses, you really need both forward and reverse lights on at the same time.
An advantage is that (at least on the BX), the headlights go off when the key is off, so you can't leave them on by mistake. Though I must admit there are times when I'd like to be able to have the work lights on when the tractor is off. I've thought of adding a parallel switch for that, but haven't done so - and I'm not sure I will.
Another tip related to wiring: Try to run wires so that there are no connections of any kind under the tractor, in wheelwells, or anywhere were the connections can get and stay wet or caked in ice. In other words, when running wire under the tractor, use a single piece of uncut wire and terminate both ends somewhere that's relatively dry.
I've been using the setup above for two winters plowing snow, done my share of lawnmowing at night, and have yet to find a reason to modify it - and it's worked flawlessly.
