CrisB, Two questions, and just be aware I'm no Off-roader like you guys by any stretch of the imagination. So if I'm not grasping this too well please understand.

1) do you need to use these fabbed plates in order for the winch mount to work on any H3? Or only with H3's that have the Brush Guard?

2) Any thoughts of designing something similar to the Winch mount, but in a 2" receiver, to make use of the front end for different hitches? Similar to the H2 front receiver? It would lift the receiver up over the front plate a bit, but utilize the chasis/frame for mounting as the winch mount does where the Tow hooks are bolted on now.

As far as strength goes, well the rear receiver, is just a bumper with a receiver mount as part of it, and the bumper is bolted to the chasis; So I would assume that there would be no reason to think that the front would be any different.
However using your design, it probably would be stronger because instead of using the bumper, like the rear, we'd be mounting the piece directly to the frame through the tow hook attachments.
Now the tow rating would be based soley on the mount's steel strength, not the truck's stamped steel bumpers strength.

What are your thoughts? I've also sent you a PM about this.