Cool truck.
I'm a committed (or maybe should be committed) IFS guy. It's definitely not what's holding me back. If I was to do a SAS, I would seriously consider doing the swap like Steve Schaefer down at Sonoran Steel did his 4Runner. Spring under axle and still stuffs 35" tires in. I hate that with a SAS you are looking at 4" minimum lift and you're still only riding on a 59" axle width. He must be riding on the lowest center of mass truck riding on 35" tires in the USA. Perfect.
I would go one farther than Grim, unless you are making primarily a crawler, I would skip the SAS and stick to reasonable mods. Spend the time and money on other stuff (fridge!) and buy lots of gas to go places. Doing an SAS correctly is not cheap and a poorly done one is a reliability nightmare. Beef up the steering, IFS truss, BJ spacers and 25mm torsion bars. If you find you are breaking that a lot, then maybe consider an SAS. Just my $0.02.
Still, grooving on the 4Runner, I like the 1st gen with the removable tops.