Well, I have this set of hole saw blades. There they were just looking forlornly up at me from my drill tool box. Couldn't help myself.

Pic 1 - layout of 4 holes on each elevator (saved .6 oz)
Pic 2 - finished lightened elevators
Pic 3 - layout of 3 holes on rudder (saved .4 oz)
Pic 4 - finished lightened rudder

Total weight savings is 1.0 oz. (using digital postal scale). Should reduce firewall weight by 3 oz.

Can't hurt. Hey, everything is a learning opportunity.