The problem with drilling is the risk of a spark.. Obvious even if tank is empty fumes will explode.. alternately force on the cap by the unknowning cloud seperate the guts with the latches, springs & cover part from the main part of the cap thus droppinside the cap and causing obstruction and roll about.. might be worth $5 to take it to a lockie and get it picked open to be safe..
Failing all the above - try a sizeable chunk of C4 plastique with a good "time delayed det".. might give U extra time to run the F^&& away - at least the problem will no longer exist (neither will the bike) He he !!
Have fun and a great day
Regards from a "Marinised" retired Lockie.. down under