In 2002 he was more along the lines of 275, not that unheard of for him to play LB in the 3-4 (See Willie McGinnest - PAtriots)
Here a quote from him before he got drafted about how some scouts and analysts say that he might end up moving to OLB.
Julius Peppers: It doesn't matter to me .. I can play LB or DE. Only difference would be the learning adjustment. But that wouldn't take long at all