4x4's dont use wheelie bars. If you want to turn that m715 into a mean machine without spending the thousands of dollars for a 1500hp big block and custom tube frames etc... then this is what I would do if you have the funds to do it: For the axles I would use a set of 2 1/2 ton rockwell's. you will not break them. Thats the same axles the actuall monster trucks use and even with putting almost 2,000hp to them....they wont break plus they are fairly cheap for what they are. If you are going to keep your tire size smaller, like 40" MAX then a pair of DANA 60's will work just fine as well but are almost as expensive as a set of rockwells. For the engine, I would use any GM big block that you can get ahold of. For tranny I would use an sm465 or TH 350 if you cant drive stick. Transfer case is the NP205 and is a must for big axles and big power. Their are other transfercase's out there that are awsome as well, but for the price and for matting it to the GM drive train....you wont beat it. Susption is a toss up really and all depends on your likes and what you want to be doing with it. If you just want to drive over cars and stuff like that....then I would use leave springs since they are cheaper and you wont really be needing anything speacial in that area. If you will be rock crawlin and actually utilizing the suspention, they I highly recomend a triangulated 4-link front and rear with full hydro steering and coilovers. Also, take into consideration when you start the build as too the size of tire you want to run. If you want to make it a beast and run 40"+ tires, then size your suspension to that. Meaning, if you are only wanting to run 35" tires, then you will not need to have a truck that has 12" of lift. Just enough lift to clear the tires at full compression when you are articulating. Meaning flexing your suspension out. The lower you can keep your center of gravity, while still maintaining a large tire is best way to do it. I can go on and on but I'll stop now lol I dont want to start rambling. A good source is to google what you want and you will find tons and tons of write ups about people doing the exact same thing.