I've done similar with my saw, the only difference is, that I cut a hole in the tray where the dust falls. Now when I use the saw, the dust falls through the hole into a container that I have attached to the underside of the tray. It's a godsend, I never have to clean up due to scrolling. The dust and scraps both all go into the container, the only cleaning up I have to do, is the emptying of the container. The container I use is 6"x12"x24", I have it set-up so that it slides in and out of the space.
Len