TRD OR suspension with steel bumper+winch

Hi folks,
I know there has been plenty posted about the impact of a 160lb+ increase on the front causing ~1" or so of sag, but I haven't found if this also applies the same for the off-road suspension. my understanding is that the springs are over 700# progressives but the shocks are valved softer.
I'm using an m8000 w/ synthetic line, and I'm looking at the c4 full hoop(and the basic c4 rear). I would -prefer- to not change out my 25k mile off-road suspension since I don't get crazy with the truck, just A to B off-roading (roads of Montana) not "recreational off-roading"
I figure I could sell my stock parts if need be, and I'm not one to go half-ass to save 20%, but again I don't care to do anything major with this truck, and I have another 4runner for the "fun" stuff.

Thanks for input

# the rest of the truck is basically stock. I'll probably be swapping tires for some 265/75s soon because my observation is that the wrangler adventures are garbage.