Actually in the span of the last 2 weeks, my grandfather and uncle died in New York so I've just made 2 huge road trips. I did pass through Maryland both times though. I'm kind of road tripped out.
I didn't replace the siding, but I did work on the removable table on the right side which is very sturdy/heavy. It also has tabs to hold the grill in place.
As far as putting another sink in, or changing this to a 3 or 4 compartment sink, you can see that the whole sink area is riveted onto the side. If you drill out the rivets and remove it, you can replace it with the replacement and rivet that on there. My guess is you could buy a sort of sink replacement kit from any number of cart manufacturers or you could build it yourself.
You'd basically be replacing the fender on the right side of the cart and replacing it with a wider sink area, or adding a sink to the other side, which would mean you'd have to do some further plumbing under the cart.
If you don't feel confident about doing the repairs yourself, you could pick up one of these...
http://www.northbendoriginals.com/sinks.html
<message edited by ptireland on Sun, 05/2/10 9:01 AM>