Winternacht

I have a 2006 F150 XLT Supercrew with Stock Tires. I want to go to either 33 inch tires or 35 inch tires. According to the guys at the tire store my stock tires are nearly 32 inches so a 33 inch tires wouldnt be much of an upgrade. But when I asked about a 35 inch tires they said that even with a two inch lift, they would probably rub. Anyone have any idea what size tires I can go up to without a lift and on that same note, would 35 inch tires work with a 2 inch lift?