A definite "How Not To Be Safe" example! Judging from the condition of his hand when he lit the propane torch, it looks like this unsafe method has already bit him at least once. Looks like he didn't learn his lesson from the first time.
Please keep further conversation on the topic of fuel tank repairs to safe methods only. Stovebolt strives to foster safe work on our trucks so we can all be around to enjoy them. Lets not give anyone the idea that this type of unsafe act is condoned or supported in anyway please and thanks!