I see - you already asked this same question in the M715Zone.com forum - and also the responses to it.
It seems to me that there isn't too much demand for any such adapters, for a company to have them readily made.
I think the most logical option would be to swap the hubs to end with the 8-on-6.5" bolt pattern. Otherwise I would just recenter the HMMWV wheels.
(if I knew the backspace- and could confirm the bolt pattern (6-on-7.25" ??) of the stock M715 wheels, then I would gladly post an exact drawing of the modified HMMWV wheel, for this application.)
The simple answer is to order the OD inner/outer wheel powder coat option re-centered HUMMER rims, mount your tires on them, and try to sell the rims outright. I did not opt for the rock rings. From: http://www.trailworthyfab.com/12-Bolt-Hummer-Wheel-Using-Flat-Centers.html If you call them, they already know the M715 Specs for their rims. They may even be able to sell you just the centers if you have someone that can accurately weld them in the exact position to make sure there is no vibration. trailworthyfab.com guarantees their rims for no vibration.
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