There is probably 1/4" to 3/8" contact surface around the perimeter that was epoxy’ed. There are no fillets. A heat gun to soften and five-in-one tool and at will pop off. Note you are moving the gun not holding in one place.
Cutting with dremmel tool will take linger and leave a rough edge to be dealt with.
Ps…old knees don’t kneel well. I can see why they put seat in. Lower CB. with a double blade.
The offending seat has been removed! I am one very happy camper right now! As the photo shows, I still have a mess to deal with, and the inside will never look perfect, but it’s good enough to paddle. I’ve already temporarily installed the original seat so I can use it and will deal with the cleanup in the coming days. A kneeling pad will be covering it all anyway.
The heat gun and a butter knife did the trick. Before heating, I placed a piece of carbon felt over the hull and up against the seat flange. During the process, the carbon fiber seat deformed a bit but looking at it after cooling, it appears perfectly useable again. You can’t tell anything even happened to it.
Thanks to all for your interest, help and encouragement! 
Looks good. I would be pleased with it. Better outcome than reselling it. Great canoe. If you do sell someone will have the option if they want.
Nice result. I’d call it done since I’d always have a kneeling pad over that area anyway. I suppose you could glue in a “permanent” mini cell kneeling pad as another way to cover the minor blemish. You were smart to heat the seat instead of the hull. I recently shortened a couple of carbon fiber paddles and was surprised at how easily the grips come off with a little heat…the carbon fiber really seems to soak up heat and retain it.
I finally got to paddle it yesterday. I am one very happy camper.
Also, I mentioned earlier in this thread that I had written to Swift to ask for advice but acknowledged that as a second-hand owner, Swift didn’t owe me a response. This morning I received a very nice email from their customer service telling me the best way to get the seat out was to cut it out and then sand down the remaining mess. I explained how I got it out, but that is not the point. The point is that Swift’s customer service is excellent if they’re willing to advise a second-hand owner about a risky proposition. Great company. 
