Why? What was a problem?
Seat surface size/shaping and padding material has a lot to do with how long I can comfortably stay in the saddle before my butt starts hurting.
Mustang compared to OEM...a little larger and more comfortable
Mustang compared to a touring saddle from my Valkyrie...I can spend much more time on the Valkyrie seat before needing a break.
A large comfortable seat on the small Rebel would not fit the bikes style