FSR,
A couple things to think about. The Nissan axle is as tough as a Ford. Gears may be cheaper, but do you REALLY need gears with a 4.62/1 ratio? Most Jeeps would bust a nut with that gear. If you get as close as you can to that ratio with the front Dana 44, you will have a monstrocity. Your problem is horsepower, not gear ratio. I would save the money and time on the Ford 9" and invest it in an engine combination. If you get the hp up, add in a crawl gear and dual lockers, you will have a serious @#$kicker even with 35" tires! Also, most hard core off-roaders use a 6 lug pattern on their trucks. The reason is for strength with the bigger tires. The extra lug spreads more of the torque applied and reduces the likelihood of busting lugs off. Something to think about.