Corbin seats vs. Dino Hinge
I don't know if the Corbin seats from 2003 will fit the 2004, but I imagine so.
One thing I have to pass on is, the newer Corbin seats are pop-riveted around the perimeter, whereas the older ones apparently had the cover stapled down.
After going through all the other steps to fit my Dino hinge, it became apparent that I was going to have to cut into the seat. I didn't really want to do that in the first place, and there's no way to get the seat cover back down if you drilled out the poprivets and stuff.
Dino was cool and let me return the hinge, but in the meantime, I now have no helmet lock wires or hooks, cut up the plastic box inside, and had to bend the attaching point to achieve "alignment." Just something to consider if you're thinking about a new Corbin.