I talked to the guy at the welding supply today... if you plan to transport any cylinder away from the store inside an enclosed vehicle, you have to sign a release of liability waiver before they will sell you the gas...

Obviously they want it transported in the open outside the vehicle.. so a pickup as you mention would fill the bill..

He gave the impression that the laws and fines are more applicable to larger cylinders and mentioned that they stay away from the larger cylinders for that reason.

btw they had a large poster on the wall with pics of three vehicles blown into an unrecognizble mass from welding cylinder accidents.. None of the vehicles were burned by fire.. just the force of high pressure release....no details of course..

Still would like to hear from someone who's really up on this subject... others??