#1) take it easy fellas re: PVC
#2) An extension on the cabinet can be as easy as putting your object in the cabinet, leaving the door open, then taping a big bag or plastic around the opening. OR, as extensive as building an extension box out of wood or metal and using a stick-on foam sealer or a commercial truck cabinet bulb seal. It's just a matter of how much work you want to put in to it or how much permanence you need. I had a co-worker leave the door open and velcro a soft mud flap to our cabinet to minimize the amount of media lost. Then he would sweep up the escapees, sift them and reuse.
