I modified a 17' Egret SOF to handle a 21lbs Sheltie.  I decided to place the Dog-pit in front of me, basically between my knees.  I wanted him out front so I could keep an eye on the little monster however did not want create an inbalance and have too much weight up front hence kept him in close.  I would recommend for a dog the size of a golden to enlarge the rear hatch and have him behind you.   That much weight up front without balancing it off in the rear will cause the boat to loose some directional stability. 

I think all you need to do is enlarge the rear hatch, add a coaming (helps keep water out) and craft a new hatch for those solo paddles.  For Elf, I have a doggie hammock that clips in when the hatch is removed.  Though you will not have as much of a need for this because you are dealing with an S&G, I would still recommend it.  It keeps Fido in place, the waves out and this way you will still have some storage should you want to pack some snacks.  I am happy to email you pics.  david at dragonsong dot ca

Have you had your dog out in a boat before?  I did some test paddles in a canoe to ensure that he would like to come.  Now I cannot keep him out of the boat!

Thanks for the reply. I would be interested in pictures.  I am trying to envision the "hammock".  Is this like a cockpit cover that sags inward? 

 I've paddled with a golden retriever in a canoe before. It didn't work out well because the dog was full-grown, but still adolescent. Too much energy and not enough training!  She had never been in a boat before and moved about too much.  We are now starting out with a very young puppy and I hope to put emphasis on good manners in a boat/kayak.  As I am past the stage of training children, I should be able to spend more time training the dog.

I've thought about boat balance as it relates to the dogs weight. The aft hatch does seem like the best place for the extra weight, but I am concerned that I won't be able to see the dog, and the dog will be trying to look around me, throwing the weight off-center. 

no experience with dogs in kayaks,  but, having had a golden who passed away last year, he would love it and stay put as long as he knows "stay" or something similar. They love the water whether in it or out of it. Good luck!

I did a couple of short day trips in calm water with a miniature aussie in the back hatch and it worked OK.  However, there were a few weight shifts that were dicey and that is with a 25# dog and small legs.  I can't imagine what would happen with a bigger dog if he got excited and shifted quickly from one side to the other, or maybe I can imagine too well.

Hopefully picture link attaches

Thanks for the reply.  The issue of weight shifting as the dog moves may definitely be an issue. I'm playing with the idea of adding outriggers (amas) such as the CLC kayak sail rig has to stabilize the boat.  I don't believe that they would have to be very large or offset very far from the centerline of the boat.  I appreciate hearing that a 25 lb dog was enough to cause balance problems. 

Bill