Not to bring this back to the top or anything..but I was given some drawings by Honey Bee becuaes I Plan on makeing a few models and all the drawings appear to be 42ft on center. 21f reels on both sides and everything. Unless he marked it up wrong Im not sure. THe offset would make more sense though as Im not sure how much room you would have between the header and cart when unloading. Isnt the auger only 12 or 22ft?