Removing 2nd gas cap

[rocketBox]

First post here... I've got a 1970 f250 cameet special. It's in good running condition and generally good cosmetic condition. I purchased the pickup about 18 months ago, done some maintenancy such as starter replacement, solenoid replacement, oil change and other misc stuff to keep the truck running smooth. I'm certainly not unfamiliar with wrenching. The whole time I have had the truck the Secondary gas tank cap has been locked. Is there a way to remove this cap (the tank under the bed, not behind the seat)? My thought was to remove the joint between the filler tube and the tank and drill it out, but I was wondering if there is a better way?

[Subzero]

If it's a locking has cap there are ways to "break into" the lock. YouTube has videos of how to do it I think. They're not too strong locks, just meant to keep prying hands away