320 Install
I have a 2001 320, which is basically the same boat as your 326. I installed the Raymarine GPS, which is the same as Hunter would install at the factory. This keeps the interface the same (Seatalk, using ST 40). The only thing I did different was mounting the antenna on the arch rather than down on the rail. It is completely out of the way, but drilling the hole took a while. I also cut off the connector at the end of the antenna lead (Raymarine says not to, but I kept the length the same, and soldered on a new connector. They should sell the unit without the connector to make it easier to run the cable.) You will also have to make a wedge to keep the antenna level. By the way, the GPS can also interface with your VHF to give off DSC positions for a Mayday.For the invertor, I bought a refurbished unit from 2500 Powerstat off their website. It was a couple hundred bucks cheeper than new, and I had no problems. It is mounted under the port lazerette in the main cabin. These things kept me busy last spring waiting for the ice to melt so I could go sailing.Good luck, and enjoy the boat.