</font><font color="blue" class="small">( . . . Basically what I was intending on doing with this is making a mount that would fit into the Quick Hitch on my 3pt hitch and then have a electrical quick disconnect for the power. I am pretty sure high amp alternator on the
BX23 puts out 40amps - how much does the usual ATV alternator put out? . . . )</font>
There is a safety issue in long runs of unprotected high capacity wiring. Here are a few things to consider.
The alternator isn't going to run the winch, only recharge the battery. A high capacity alternator will be quicker in recharging the battery. The battery is going to do the work.
You might think about doubling up on the battery. That is put another battery in the rear of the tractor, possibly as part of the winch set up. Run lines to charge the second battery--not run the winch. Make some more bracketry to carry the battery.
To run a winch (at 100+ amps) you need wiring the size of car's starter wiring from the battery to your disconnect location and then to the winch. Frankly that size wiring from the battery to the back of the tractor is just looking for trouble. There is no convenient (read small) way to fuse a line of that capacity. Pinching the line to the frame and grounding the hot wire is going to happen sometime on a tractor. It'll be a guaranteed disaster if the line isn't fused. If you choose to run heavy lines the length of the tractor please be sure to work the fuses into the line near the battery.
With a separate battery, you only need wire size to support recharging the battery. You can get in line fuse holders for 30 amp fuses readily. A number 8 wire should handle 30 amps and can be routed inside the frame (for protection) easier than starter wiring. Run a ground wire from the battery too, don't use the frame for currents that large. Tie-wrap the wire securely, vibration chafing can be a real problem on a tractor.
Of course you could place the quick disconnect at the front of the tractor (near the battery). Then run temporary long jumpers from the winch to the QD. But, that carries the danger of a pinch ground too, but at least it wouldn't be there all the time. Still not the best choice though.