Provided you don't have inspections, the whole thing can be removed, BUT you must plug/block the hole in the head to prevent a BIG exhaust leak.

The old backyard method is to cut off the tube a few inches from where it bolts to the head and pinch it shut. You can just see the one on the van. It was done way back by someone else.

Considering those rot and are no longer available, you might want to save it and sell to someone that does have to pass inspections.