That's the first I've ever heard carrying extra fuel is illegal. I suspect there could be some issue if you were carrying a can without a CARB stamp in some jurisdictions. The irony is LRA won't sell you an aux tank or replacement tank if you are from California.
#1 Replacement 40 gallon LRA main fuel tank. Hands down my favorite modification to the 100. It "fixes" what I consider the achilles heal of the 100 series: range. It requires no fancy bumper with a swingout, no high dollar roof rack, no lifting gas cans over your head, no potential thievery or...