the rear fender is getting replaced with a custom i plan on beating out sometime this summer. sadly, the hidious suzuki saddlebags that came with the bike will no longer fit on there

i want to mount saddlebags over the frame and underneith the seat. They would hang down over the airbox on either side of me arsewhile im sitting on the bike. They would have to be soft or shaped correctly as to not get in the way of my legs while im stopped, but still have some support for the belongings within.
Has anyone heard of this arrangment before? do you know of a brand of bag that would be up to this modification challenge or should i attempt a complete custom?
i think smaller, non-angled bags are an obvious choice.....