I have done just this, VX...check, tires...check, overland...check
I have OME 919's and they fit with a little T-bar crank (do alignment afterwards). I trimmed the front right off my car and added a tube bumper. I would try a lighter tire than the BFG I have good luck with General AT2s as they are the same BFG pattern just spaced further apart. Keep the stock wheels or something with similar backspacing.
BTW the VX isn't a good overland option as they are hard to find some parts for, lack space, lack cup holders, aftermarket isn't great, but if you need something with a wow factor or conversation starter it will work great.
I have driven from Alaska to Baja and this October will be doing AZ-Maine, Maine-FL, FL-AZ
http://www.expeditionportal.com/foru...land-VEHIcross
Hope this helps at all...if I could do it all over again, I'd do it with an older Toyota, alas I've fallen in love with the VX
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