I suppose you could do something like this around your C-notches and of course your going to have to leave room for your fenders. Make it out of wood so it matches the bed I guess.
http://images.minitruckinweb.com/con...custom_bed.jpg
Build a bridge and do something like this if you want. However I think it looks unfinished myself with it in the middle.
http://images.minitruckinweb.com/tec...thout_Tubs.jpg
Maybe don't notch it as much and bend up some metal over the entire thing.
http://image.automotive.com/f/featur...custom_bed.jpg
Sure a shallow bed doesn't look as good, but it does in this photo and you still get the full use of the bed.
http://www.supafly.com/images/journa...evy_Truck6.jpg