Yeah, in regards to the truck.

I measured that I have 0.75" of clearance from the front tires to the fenderwell corner at the worst spot. I have 275/60r20, 1.5" spacer, and bilstein at 1" lift.

I am ready to mount 285/60r20 tires, they are 0.5" taller and 0.4" wider, so they theoretically would take up 0.3 or 0.4" of my 0.75" clearance, leaving only 0.4" maybe. Worried about turning up hills or whatever, should I adjust the bilsteins up another inch or am I OK running this?

Looking for opinions. It would be easy just to not take off the struts again to adjust......

 

That was so ripe for the picking....
I think you'll be OK as clearance goes. You might get a touch of rub under just the right conditions when wheeling, but I'd prefer that to the over-stressed ball joints & CV's you'll have with 3.5" worth of spacers/strut.
EDIT-- assuming factory wheels, you'll be fine. My Son has a 2.5" level on his '05 and runs 285/75-18's which are well over an inch bigger in diameter, and it only rarely rubs lightly when things are just right.

 

 

 

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He has the adjustable bilstien shocks, set at the 1" setting. No spacers on the shocks.

 

 

If it rubs a little, ditching the wheel spacers will fix it. I am personally NOT a supporter of wheel spacers. Many years ago I drove AAA tow truck for a large/busy contract station. In those years (nearly 15) I saw numerous cases of sheared studs and thrown wheels due to spacers. I know a lot of people will argue that they're perfectly safe when "installed correctly" but I know what I witnessed. I towed in a chevy van with a caved-in windshield from an oncoming F150 (older 5 lug) that pitched it's wheel at just the wrong time. Fortunately nobody was injured. They're also hard on ball joints, hard on wheel bearings and cause the truck to throw rocks outside the fenders.-- Okay, I'll get off my soap box now...
A thought on the Bilstein's, assuming you decide to go higher. I just put them on my '13 and set them at 1.5" (the increments are different on the 12th gens). The ride is noticeably stiffer due to the increased pre-load. If you were to pull the struts (yeah,yeah I know...coilovers) back out, you might consider going to zero and then using a conventional 2" leveling spacer, depending on your preferred ride firmness.

 

^Agree with everything he said on spacers. Save the bearings and the lugs!