Because of the number of attachments we build and sell from other manufacturers, it's hard for everyone to know everything about them. Yes, this is something we maybe should know, but all of us are quite reluctant to tell people how to make something QH compatible if it wasn't manufactured as QH compatible because many factors can come into play. We are constantly on the phone from opening to closing, so it's hard for us to get away and research some things, especially if a tractor is not here with a quick hitch installed at the time. Attachments generally ship out very quickly after we make them, so, most of the time, an assembled cutter is not sitting around to get measurements off of.
Hopefully this helps explain his predicament.
I'm glad you got it hooked up to the QH. We'd love to see pics if you're willing to share!
Travis