Wayne Parham Messages: 18884 Registered: January 2001
Illuminati (33rd Degree)
We've run into this before, occasionally the port tubes are made slightly larger than spec. The added strength from greater thickness is good, but it does make OD slightly larger. It's best to use an adjustable hole cutter and set it exactly to match the duct. Honestly, the best and easiest way is to cut new baffles, I think. But you may be able to open up the port cutout slightly to fit the thicker tube in place.