Would 1 inch front lift plus bumper cut fit 285s?

Will I be able to run 285s with 1 inch spacer in the front with viper cut?

 

I think a lot of that depends on wheel offset. Probably more likely with factory wheel offset and an alignment that favors pushing the wheels forward a bit. I hope to find out soon, although I have a 2” lift up front.

Always a good reference:
https://trail4runner.com/2018/01/03/largest-tire-size-4runner/

 

^^^This^^^

I believe people have fit 285's on a stock PRO, which sits about an inch higher in front.

A fender liner modification, wheels with the right offset, and a good alignment with maximum caster "should" do it.