Your unappreciated zinger about being an old ARRL type notwithstanding, you may be under the (mis)impression that I hadn't considered the proximity problem.
Also, something else you may not have realized was that the LPG tanks are not exposed. Rather, they're covered by a well-grounded metallic cover.
Never had a lick of trouble, and don't expect to. Ever.
Explanatory photos available at HTTP://members.aol.com/luckky1t/airstream/index.htm
Regards,
Byron Hurder, KY1T
Modern Day itinerant/migrant worker who doesn't do Apples but does do Windows