Just a suggestion- - - -the Chevy 6 bolt wheel lug pattern is shared with numerous Japanese pickups- - - -Toyota, Mazda, Nissan, Mitsubishi, etc. You might be able to find a suitable ratio by swapping the entire rear axle assembly instead of just the gears. The early Land Cruiser rear end just might be worth a look- - - -just about the right width as well as possibly a suitable gear ratio.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!