The Harmony Roto Explorer Seat offers superb durability and surprising comfort. The seat bolts directly to the gunwale providing added stiffness to the canoe. The slightly dished seat is comfortable facing in either direction for fishing, conversation, or paddling solo.
First, This is an excellent product. I like you can sit forward or backwards. The dimensions provided are wholly inadequate so: Bow seat: 31" at trailing edge. 28.5" at the leading edge by 9.5" by 2" thick. The drop is approx 2.25" so the seating surface will end up about 2.25" below the underside of your gunnels. Stern seat: 23" at trailing edge. 26.25" at the leading edge by 9.5" by 2" thick. The drop is approx 2.25" so the seating surface will end up about 2.25" below the underside of your gunnels. I went to the local salvage yard and got some extruded aluminum. You can probably get this at home depot. I used 5/8" c-channel. I cut four pieces to 11" then hit it with a wire wheel to remove burrs. I then drilled a hole about 1/2" from each end. I put the bolts down through the gunnels and into the aluminum. The seat rests on these like a saddle. This is very sturdy and was a very convenient way to do it. This way I did not need to perforate the seats. If you are going to use aluminum I would do it this way and not drill through the seats because if you need to drill the seats and the gunnels and the aluminum you may find your drill bit is too short. I found this out the hard way and it was a major pain trying to line it all up. Trust me on this one. I suspect it would work completely well to just drill the gunnels and seats and put fender washers under the seats. In that case you may be able to get away with 4" finishing screws which are easier to find. I am a bit heavy and wanted to be extra sure so I went with the aluminum as above. I used the harmony screws kit see my review. have fun!!!
Adapted nicely to an Old Town "Hunter". Good product. Recommend.