I'm upgrading my dust collection from 4" to 6" duct work and 5 or 6 " hose. All the ports on my machines are 4". Rather than choke the collector at the source, I plan to use larger ports. The first will be on a Powermatic 66 table saw. What is the best way to cut a 6" diameter hole in the metal cabinet? And what is a good source for a fitting to connect the saw to the hose?

Many thanks!

Len