Not sure if you are talking SRW or DRW K30..., but either way you will likely rub 35s on stock suspension.
But I fit 285/75R16 tires, (33x11.5) with no modifications on stock offset wheels, I had no rubbing at all. Then I put on 315/75R16 (35x12.5) and I did get rubbing when turning and flexing the suspension over bumps. I put 4" springs upfront and now have no rubbing, even after putting 1.5" spacers up front for a wider stance (basically the same idea as putting wider offset offroad wheels on a SRW truck).
One thing you have to your advantage is that BFG tires generally run small. Those 35" will likely measure barely over than 34". If you run them on stock wheels you may be ok, but if you put them on wider offset wheels you will definitely have rubbing problems.
Here are a few pics of mine for reference
33s on stock suspension

35s on stock suspension

35s with 4" springs up front
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