Why not run a Dana 70 for the rear??
Pros: Cheap everything, ground clearance, plentiful, mega strong (like the sterling)
Cons: you don't have one yet
as far as the 8.8 being strong, I had 28 spline axles (stock ranger axle) rocking 37" Iroks and wheelin it pretty hard, not to mention towing 13K lbs (my buddy's broke K5 blazer

) for about 50 miles. I swapped to an exp 8.8 mainly for better brakes and the L/S, but also gained more strength with the 31 spline axles and bigger housing...I'm currently building an 8 lug D44 for the front and FF D60 for the rear, only cause I got both axles for $100

but I wanted a D70 for the rear...It all depends on which route you go for the front, if you go D60, then you'll want to match it with an 8 lug axle, prefferably the 70, but a FF D60 will still be plenty strong, as this axle is behind 3/4 vans with powerstrokes and no problems...Besides, with a 2.3L, you'll need a turbo and dual tcases to turn those tires rock crawling, I'd go as low a gear as you can. Speaking from experience, you need a lot of gear when you crawl, and a small motor only makes that need that much more.
SVT