this... On tractors, the alignment of the dogs can vary as you lift the blower
Isn't correct IF the drawings I've seen here years ago, from the install manuals are correct.
the dogclutch is on the blower side of the pivot point where the Ujoint is. Once engaged, the clutch can't move,physically impossible.
I spent a lot of time looking into this and concluded it's the actual $700 dogclutches of dubious quality. Every picture I've seen show a 3 tooth dog with maybe 50% overlap compared to a $100 Lovejoy that has 4 teeth and 100% overlap.You've got up to 20HP coming from the PTO, so you need proper parts.
That's what I'd like to see, the actual 'connection' between tractor and blower