your running the same tyres that i am . 33x12.5 bfg's
How much are your torsions wound up? Have much down travel do you have?
First i fitted a 2inch body lift, 3 inch suspension , only rubbed very occasionally on drivers side back of guard under hard compression at full lock. ie dropping into a hole drivers side.
Was stiff as hell and had virtually no down travel in the front and always lifted a front wheel, blew 3 Cv's with this setup.
Then dropped suspension lift to 2inch , wound down torsions a little , had to take a BFH to rear of guard to stop rub at full lock / compression on both sides.
Suspension worked a bit better like this and only did 1 CV. rear suspension working alot better.
Know i have dropped suspension to 1inch lift. front torsions are set so bottom A-arms are flat. Tyre clearance only by body lift.
had to hammer guards some more to stop rub.
suspension works best it ever has. not stiff off road. rear is not trying to do all the work.
As for adjusting bump stops in the front , IFS surfs only have about 100mm of travel in the front total. IMO i wouldn't be reducing the limited amount of travel more by lowering the top bumpstops.
If i was going to do it again i would just cut the offending firewall away and weld in some new plate , clearance issues sorted with no body lift.
body lift also lifts the radiator , lifting the bottom tank out of the way and protecting it behind the cross-member at he front.
body lift lets you work on and clean stuff so much easier as well.