BEST lift or best lift at a certain price?
You can get prerunner I-beams for the front, along with extended radius arms, and the correct lift springs and shocks, (or even go with full coilovers). Cost depends on where you get it, you can get everything from a budget kit for a few hundred that is just modified factory parts to well over a grand for completely new fabricated parts.
You can get OME (Old Man Emu) Rear leaf springs that lift the rear 2.5", and get some additional lift if needed from Warrior shackles. Price is pretty hefty, $500-600 or so, maybe more. Usually a rear budget lift is an add-a-leaf (~$25) along with the Warrior shackles, which gets you 2-3 inches, but can ride a bit rough.
You're going to have an issue putting on larger tires with 3.08 gears. Those are best with the stock 225/70R15 tire size. Even the larger 235/75R15 or 30x9.50's will make it really slow.
The first money you should probably drop is for new gears, since it's not too bad on a 2WD, you just have the rear diff. You can get stock 3.73's rather cheap from someone on here who's changed theirs out, or you can buy a new ring and pinion for ~$100. You might also just want to swap out the whole rear axle if you find an 8.8" that has a Limited Slip/Trak-Lok diff with the gears you want, too. A whole new axle can often be much less expensive than paying a shop to swap gears.
With 3.73 or 4.10 gears and the 2-3" lift, 31-32's should be fine and you'll gain a good bit of useable travel if you've used quality parts.