drmiles: I consider myself sort of an expert on hitchs, having fabricated several. Recently i fabricated a custom fully hidden hitch for my mustang GT. Came out awesome. Unless you crawl under the car you cannot see anything.
Back to your problem, when you extend the hitch you increase the twisting load on the reciever. Think of the drawbar as a lever, when you have it very short you have no leverage.....but when you extend it you increase the leverage, making it easier to bend the reciever on the truck. heck, i would bet if you extended it 8 feet (Silly!) you could proboly bend it just by jumping on the bar! Im sure theres a formula somewhere that would figure out bar length vs weight it takes to bend. I have an atv carrier I have used behind my h2, it extends proboly about 6', with my 400 lb atv on it and my hitch still hasent bent. So im wondering if you have more tongue weight than you think. How do you know its 2000 lbs tongue weight? Get a tongue weight scale:
http://www.sherline.com/lm.htm (thats the one I have works *AWESOME*).
The good news is, I deal with a lot of towing.....personal and business, and I have *NEVER* seen a reciever hitch "snap". They bend....but never break (Must happen now and then to someone but VERY uncommon).
I tow my stacker (18,000 lbs) now and then with my H2 and the tongue weight is around 2,000 lbs. When you tow anything heavy you MUST remove the spare tire and use a standard length bar. If you get a bar with enough drop and if the trailer doesnt catch you may be able to do it with the tire in place. I can tow my snowmobile trailer with my spare tire on.
Wouldnt be too hard to mod the tire carrier to lift the tire a bit higher for clearance if you wanted to....
Anyways....
--John