With the firepot attached, yes the ash drawer (with the base chamber) is the heaviest.
I would guess that the ash drawer and firepot, with the back pipe base, striped of all loose parts, is about 120-130 pounds. I can just barely lift it off the floor an inch, or so. Not sure I could do the same if it was from a #8.
The barrel, striped of loose parts, with door frame, top, and the back pipe dome, is only about 40 pounds. The grate bars in their rack is close to that.
After we removed all the loose parts, it took Wilson and I both to lift the barrel, firepot and ash drawer off the base (the part with legs) before he unbolted the barrel from the firepot.