Found this while looking for a hitch.
https://www.logsa.army.mil/psmag/archives/PS2014/738/738-17.pdf
It references a mortar stowage kit NSN 2540-01-623-6327 that contains an adjustable lunette ring. It is intended to adjust the lunette higher to attach to larger trucks. Not sure if it can be flipped the other way around. Or if it is even obtainable. Thought it was worth mentioning. Including a screenshot for convenience:
https://www.logsa.army.mil/psmag/archives/PS2014/738/738-17.pdf
It references a mortar stowage kit NSN 2540-01-623-6327 that contains an adjustable lunette ring. It is intended to adjust the lunette higher to attach to larger trucks. Not sure if it can be flipped the other way around. Or if it is even obtainable. Thought it was worth mentioning. Including a screenshot for convenience: