Rolling like Clark Griswold?  The Motherlode wraps around your passenger seat to create an XL (20" wide, 15.5" front to back) sized platform, complete with strap loops and hooking points.  1/8" metal plate. 
 
An optional helmet lock with tamper proof hardware can be mounted to either side.
 
Offered in a durable sand black textured powdercoat. Comes with stainless hardware.