hi, i have a 2004 scamp
13. i have the 12 gallon tank that i pulled out because of some other modifications. i posted it a couple of times but the folks who were interested and had older scamps found that the tank height was too high for either the seat or the fill pipe. i bought replacement tanks with different dimensions for my application from the usplastics and plasticmart. you might take some measurements and give them a try. installation is pretty simple.
in my case i had to use split tanks but it still works fine.
jon from sequim