
This locking gas cap is the best I have found for my 1978 Jeep J20 truck. The non-blocking version just doesn't fit. However, this one (Stant #10592) fits. Not great, but it works. Its a wobbly fit and latch, but you can tell it's not perfect. Not sure what's wrong with those old full size jeeps that are hard to put on gas caps, but finding something to fit was CHALLENGE. I'd recommend this (it's better than an old rag in the tank), but don't wonder what "seems to fit" in your setup.

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