Their website shows a Hi-Lo/ TrailManor style.
http://www.adcoprod.com/sfs_aqua-shed_hi_lo.htm
I am not home to check which one I have, but the length of the box is the only variable with the TM. They are all the same height and width.
Mine covers my spare tire and my propane tanks. I like that. But my TM is a 2518.
Sounds like you need the 26 ft box length. Looks like thats the longest they make in that style.
Cheri