I took delivery of my new 1026R with 54D deck last month and had no need for the deck to be on so I took it off. As luck would have it, spring came early and I needed to mow my grass this weekend. Of course the deck would not autoconnect and I had to manually push the latch bar down to engage. Even though these have been in production for awhile, Deere has not changed their design to incoporate what you "Pioneers" did with the addition of the extra washers. Like the others, I found that with the additional washer the stronger spring is not required. I have included a drawing from the parts manual illustrating what has been changed, which goes along with JRS1959's pictures above.
The existing washers (piece 9) are 10.5 ID x 18 OD x 1.6 thick mm, and I substituted 3/8" SAE in their place. The existing bolts (piece 1) are 10mm OD and a 3/8" SAE washer is 13/32" (10.31875mm) ID. Thanks to this forum and its great members, I now have a deck that connects properly. :yahoo: