Numb3rrs

So I'm wondering what sizing Peter Clark suggests we use pre-flop. In the Grinder's Manual, I remember he advocates for 3x UTG and HJ, 2.5x on the CO and 2x on the button. In the course, however, he doesn't really specify anything. I heard him mention 2.5x on the BTN, but nothing specific from other positions. Should I go 2.5x across the board or use variable sizes by position like in GM? (Obviously, I mean as a default, I might adapt my sizing based on table conditions.) I'm hoping someone can help clarify this.