Doing a solid axle swap leaves the possibilities endless. It all comes down to HOW much fab work you can and WANT to do.
If you have the money, buying the Marlin 4" SAS kit is the way to go. You get everything you need except for the solid axle and gears and front drive shaft. You can also buy their matching rear lift kit, though you'd want a 5" spring for the rear to compensate for the weight of the 4runner top and rollbar.
If I were to have the money, an IFS truck and the desire to have the nicest ride on and off the road, I would go with Marlin, hands down. Unfortunately, I am a poor college student, so I had to find the cheapest route possible.
Thus I had my friend Luke over at 4x4 Labs make me a spring hanger (I dont have a welder and I suck anyway) and some 6" shackles for the front and rear and u bolt flip kits($120). Then I went to a junkyard and sourced some Jeep wagoneer front leaf springs and some chevy 1500 pick up 63" rear leaf springs (all 4 springs cost less than $100).
Driveline wise I was able to use my rear (prior to going dual cases) but I had my friend make me a square front driveline ($50).
Most everything else I bought from Marlin (shocks, upgraded brakes, brake lines, etc) but the junk yard springs and the stuff from 4x4 Labs saved me a lot of money. Not to mention my friends and I did all the labor so that cut out that cost right there save a few 30 packs of beer.
Looking back I wouldn't change a thing. I wish I could have afforded the Marlin springs because everyone I know that has them LOVES them and I have seen how well they do on the street and offroad.
It all comes down to what you want to spend. There are endless junk yard spring options (Rears up front, chevys, waggys, F150s, S10, etc..) and that is the area you can save the most money aside from the labor cost. Check out the pirate4x4.com Toyota FAQ, there is a TON of great cheap lift ideas in there.
OME and All Pro are both quality companies as well but like others have said, I would steer away from TG. I chose to support Marlin Crawler because they are the innovators behind the dual case system and have never hesitated to sit on the phone with me for an hour to listen to my questions or help me figure out a problem I may have. Not to mention the few times there was a mistake, they were quick to make it right and always hooked me up free shwag (not just a cheap keychain, but beanies and sweatshirts) for their mistake. I can't say the same about a lot of other companies.
Not to mention... if you ever break down on the trail and Marlin happens to find you, he will do whatever it takes to get you rolling again, even if you didn't ask for his help. I've seen Marlin working on broken trail rigs more than I have ever even seen him wheeling
