285's will fit in the rear without any modifications. Your stock front Upper Control Arms will accommodate 2 inches of lift. Using your stock front shocks with 2 inch lift springs could present a problem. If your suspension fully flexes you could damage the shocks. For very few dollars get a set of Bilstein 5100's for the front, use your stock springs and level the vehicle. Roughly 1.5 inches of lift. You'll have no problem fitting 285's.
But let’s say I’ve upgraded my shock bilstein 5100 on front and back with new coil springs, approx i have 2.5” lift, could I fit bigger tires like 315/70/17 on it with a performance upper arm regardless that I’ll do BMC?
Fitting 315's correctly is going to require a substantial investment. 3 inch lift in the front, body mount chop, sway bar relocation, differential drop kit, upper control arms, 1.5 to 2 inches of lift in the rear, rims with the appropriate amount of backspacing.