So I just got my Trotec in yesterday, and I'm having an interesting issue with the exhaust port. It's 3.5" O.D. and 3" I.D., which is being connected to my Penn blower motor which is 4". The available duct reducers are only 3" to 4". I can't squeeze a 3" inside of the exhaust, and would really prefer not to. Any tips or tricks?