for frame mounted sliders, it sounds like a good plan. overkill, and twice the thickness of the frame - make sure you've got lots of gussets holding them on the frame so that doesn't turn into a weak/bending point.
Whenever I start welding up something that is going on a vehicle I consider its weight and what effect it will have on it. I've got rails made from 2" sched 40
pipe. I believe they are .188" thick. I've beat them pretty good and you would never know by looking at them. My front bumper is 3" square tubing that is even thinner and I bounced off a tree @ around 10-15 mph with no ill effects.
Salvaged 87 2 door 2.5L XJ:
Trac-Loc D44, Aussie Locker disco D30
3" lift, 31x10.50 Treadwright Guard Dog Kedge Grip
15x8 4.5 BS Rock Crawler Extreme Steel
What are sway bars?
I used 2x3 with 2x.120 tubes to the frame. When you weld the outriggers on to the frame, plate the frame with a 4x4 piece of .188 or .25 plate. Mine ripped out and I had to cut them off and go back and replate them.
Wheeled very hard for 4 years and they didn't budge at all.