fuel tank id

[jrsmith1]

I once found a picture identification chart on how to tell if you had a standard tank or a special and also the year. I cannot find it anywhere! It showed if the gas cap was on the side or middle and also if it had one petcock or two. Can anyone direct me?

 

[gggGary]

Standard tank has the cap centered, Specials are offset to the right, US tanks went to single petcock in 80 when the BS34s were introduced. Vacuum petcocks came in 78. The petcock bolt spacing changed (wider) with the vacuum petcocks.

 

[jrsmith1]

Thank you.