Mine also, is on the upper right of the fan housing. It really doesn’t matter where it is mounted, but mounting close to the generator keeps the length of the wire runs to a minimum and makes the most sense to me.
The best place is on the cooling Housing on the left side as close as possible to the Generator. I would put in an alternator if it was me. I converted mine and it is great! No dimming lights at Idle, and no regulator. You have to change the mounting base, and fuel pump and push rod. Takes about 2 hours to convert. It is just a much better system, less problems.