Just a note. the date hardly matters on a second hand system as by law it needs to be fitted or inspected by a licenced lpg fitter and a new lpg compliance plate fitted to the vehicle to be leagal. when this is done they normaly will restamp the cylinder anyway as part of the inspection. if you fit it your self its not legally fitted if the tanks in date or not.

also alot of lpg fitters wont use the second hand pipes and will insist on fitting new pipes.

the last lpg system i removed i took it to the local lpg workshop and he paid me $250 for it. easy no advetising