i THINK YOUR ON to something there. I thought the same thing. But when I tried to make it upside down the top bracket, wasn't high enough to bolt the hook onto. Now I have thought maybe if the upper metal tabs were added onto to support the hook it would work. Theres allot of pressure there. When I tried it, I could only place one bolt, and it bent the bolt.
But your on the right track. Modify the quick hitch upper metal tabs so the hook could come down onto the link.
This does defeat the hook up though, . as the original idea was to back up and hook under it. But if you would have to get off the tractor, and place the adapter to it there shouldn't be much difference.
As others have said its the lower pins that are the pain.
I would assume if someone added to the top, and made holes similar to the stock spacing, that it could be done that way. Possible replacing the bolts with pins of some sort.Which has been mentioned before.
Perhaps some side movement bracing on that as well.
Great minds at work here...