Already flipped the axle, it was easy. Completed it in less than 4 hours doing all the work without any help. Plenty of clearance now for the 15" tires.
I had thought about longer shackles but the geometry was all wrong, it would have ended up breaking a spring or some other damage. Flipping the axle is the only way to do it an maintain proper function of the suspension.
John & Mary Jo
Enjoying the adventure