Dang need to do my Lil Red, was figuring simple gree and hot water. I know in metal tank MEK cleans them !! Not sure what it would do for a plastic. Have an extra gas tank , split on corner, wonder how i can patch?

1969 Dodge Coronet R/T Convertible
1979 LiL Red x2
2012 Yellow Jacket
2006 mega cab
1977 Trailduster
1979 Trailduster