The key looks generic and easily duplicated...like those keys that are used to lock servers and PC cases.

 

Did a little research. The High Rock and Mopar doors come with a replacement filler neck so the door bolts directly to the metal neck. The rear tail light needs to be removed to get the filler neck out. No holes are required to be drilled. Very secure, except they don't lock! The Rampage units screw into the plastic (that's why they're cheaper). Not so secure, but they do lock.

Has anyone found one that comes with the secure replacement filler neck AND locks???

 

i have the mopar filler door and was thinking of buying one the locking fuel door and just screwing the new door in to the mopar frame