I have the same setup, I had to weld up an extension so the quick hitch hook could grab the top lift point. I used two 1/8 x 2" bar stock then drilled two 3/4" holes for 3/4" round roll stock. Then plug welded the two round bars into place. Then I welded a support on the top of the two 2" side bars to give it a little extra support on the side rails. I pull the tractor up to the quick hitch and from the seat looking rearward flip the extension over the hook and lift the 3pt. It works every time without any problem.
I just had a new B2601 delivered last week with this ballast box and I just assumed it would be QH compatible.....Shame on me. I think I'm picturing what you did, but is there any way you could take a picture?
Gents;
The John Deere ballast box for their IMatch system is quick hitch compatible with no modifications Model BW15073. There is a bushing package required for Quick hitch use.
Thought I would circle back and post how I overcame the top link problem. Bought this speeco QH model with the top link extender. It works fine, but not real "Quick". It will do until I have time to mod the box.