I installed a Superior Kayak skeg kit in my cedar strip Night Heron several years ago. I had pics here hosted on Photobucket but it looks like they're gone now.

The kit is good quality with clear instructions. One cuts a slot in the hull to fit the cassette/box which will fit flush when finished. Cut the slot slightly undersize and final fit the box with sanding sticks or similar tools. Once the box fits nice and snug align the box vertically inside the hull and tape it securely in place. Make your fillets and glass it in bias cut cloth of whatever you have handy. Let it cure well as you'll be getting aggressive on the outside of the hull to finish it.

The box will protrude slightly from the bottom of the hull and needs to be trimmed flush to the contour of your hull. I did this easily with a long handled carbide scraper and finished it off with progressive sandpapers grits. Its really not very difficult.

Direct the skeg wire housing through your bulkheads with appropriately sized holes, be sure to seal the inner edges of any panels you drill through. I like to seal the wire guide with Lexel and I also thread a nylon washer on each side of the wire guide as I route it through. Once I apply the Lexel to seal the wire guide I slide the washers in place on each side which spreads the sealant around giving a good 360 degree seal.

The skeg control box is also fiberglass and installs similar to the skeg box. Work out your placement to suit making sure you can service things later and the box is not going to be in the way of your knee. Cut out the hole again doing the final fitment carefully by hand testing the fit often as you go. Fillet, glass and let cure.

The control box will stick out on the exterior as its square and your kayak is curved. Trim it flush again just as you did with the skeg box using the carbide scraper. The big pull scraper really makes this task easy and accurate.

Run the wire, trim it to length and you're good to go.

The most difficult aspects I encountered doing this was keeping the skeg box plumb and secure prior to glassing it in. I finally used some minicell scraps I keep around and made a saddle that bridged the upper part of the box across the hull interior. Along with some strapping tape it worked great.

The other difficult part was making sure I was getting the skeg aligned nicely with the keel of the boat. I installed my skeg kit a few months after I had finished the boat thus was working through my rear hatch and my skeg location was closer to the cockpit than usual where the keel is not pronounced on the hull.

Its really one of those tasks that sounds harder than it really is. I've put two more Superior kits in boats for other folks now and they love 'em. My Night Heron has well over 1000 miles on it and I'm pretty hard on boats here in the Rockies. The skeg works great and I wouldn't want to do without it.

I'm getting ready to start a Pygmy Murrelet and will be putting a skeg in that one, too, although this build may be using one of Patrick Onno's slick little carbon fiber skeg kit. I just have to decide if I really want to part with his rather steep asking price :)

Now... go cut a couple o' holes in your boat :D