Am I really talking to Jack Nicklaus. I used the plastic tub because it was easier than sawing the wood and then putting it together. The fan works good. It is a 683. I have a short run to the window so that helps and quiet too. I changed the fan over to a 4 inch exhaust too. Made my own adapter out of thin alum. sheet.. Very simple set up. If you screw it up you just go buy another $10 tub and start again. Machinist's are too damn fussy, believe me I know
. Paul