I run into the same problem last fall and I have to decide on two ways of correcting this problem in the next couple of weeks if I want to get some paddling in this summer. To see how my yak would handle with an outside skeg I took a 1 1/8" x 2’x4’ foam and cut out a piece like you see in the picture and shaped it to the boat. To temporarily fasten it to the boat, so you can get it off without making a real sticking mess and to also hold it real good you need two kinds of contact cement. The first is the NONFLAMMABLE CONTACT CEMENT that cleans up with water. This doesn’t stick worth a D but it won’t eat up the foam and it also pulls off your boat when you are done testing it in the water. You coat your boat where the keg will fit and also coat your foam on the bottom side. After that dries coat the boat and foam with the FLAMMABLE CONTACT CEMENT that cleans up with lacquer thinner. Before you do this trace the shape on paper or something for a pattern for wood later. You can now put this in the water and paddle to see the changes it makes in your paddling. This made a huge difference in my tracking. The second picture I am posting is a retractable skeg I have ready to put in my yak but as yet I still haven’t decided which way I am going. Maybe flip a coin.

John