Just came from the factory on the tour, the $200 Deere bracket is now included if you order the harness. It might have to do with the fact it has autosteer. (since you kind of need a screen for that) We made our own and bolted it to the A-pillar where the old GS1 mounted. This one does look nice though.
You are talking about the old smaller GS, if you put the 2600 display on it, it is three times bigger or more. The thing about this is there is no good place to put the display that will not interfere with watching the header and everything.
The OEM bracket is really nice in my mind but they have serious quality issues. Once bracket will put the monitor in the roof another will be too low and block the header height display and then some hold the GS2 and others let it flop around. I'm not sure why you would want the display pinned against the window, doesn't seem like it would be the greatest to see and would make glare terrible.
my main complaint is blocked visability. you can mount the elmers bracket in two different positions. one where the bracket is angled toward you just behind the cab post, or in another postition where its up against the angled part of the headliner----dunno how well that would work. ill try to remember to snap a pic of it when im at the barn today.
finally got some pics of the bracket. very easy to intall---prob 5 min. using the self tapping screws that was sent with it. sorry for the pic quality, they arent the best. also, thought i that i took a couple with it folded up but i guess i didnt. thanks tom for putting me onto this.