A cheap Chinese wood chisel would be perfect. They are certainly no good on wood to begin with, so it sounds like a winning idea to me. That's the kind of thing I would look for in a .99 cent bin.
Speaking of giant screwdrivers, I just remembered that about ten years ago Horror Fraught (Harbor Freight) used to carry a common tip screw driver with a one inch wide tip. Honestly that would have worked, but seeing as it was about three and a half feet long, it may have been a bit awkward for this purpose.
I never could figure out what good a jumbo screwdriver would have been, but maybe now I know. Too bad they didn't sell a stubby version alongside it.