The 1949 through 1959 gas tank is behind the seat.

SAFETY FIRST: GM had the right idea! This tank is protected by the original heavy gauge double layer metal cab. Compare this with some people's idea of hanging their gas tank behind the rear axle with very little protection from a rear end hit.

REMEMBER: The 1972 Ford Pinto that was rear ended in the mid 1970's, burst into flames, and the three Pinto passengers were killed? Yes, it came with an unprotected factory installed rear mounted gas tank! Check this on Google!

IMPORTANT: If you place the tank behind the rear axle, you also have no place for a spare tire! What Now?