way back when in my nos days, i had my bottle mounted under the bed with a thermostat bottle heater. it was mounted to the frame rail forward of the front drivers rear leaf spring perch. i took the thermostat switch off one night and the bottle got too hot. pressures got a little too high, but never blew the safety cap. even if it had, it's outside the cab. on good nights, some unspecting generic motors owner would faintly hear a purge and see nothing but tail lights. good luck and have fun