This was not placed using a kayak and to be fair I can't see how this will be possible using a kayak but there are some very agile cachers out there. I look forward to the logs as to how it was found.
Finding the general hiding place wont be difficult but reaching the log will be. The container is secured in place so please dont try and remove it. Just open the container and sign the log.
Given there are a number of options regarding which watercraft to use I haven't suggested launching points or types. I will say that for anyone who doesnt have access to their own craft the National Trust hire boats of various sizes at Crom.
http://www.nationaltrust.org.uk/crom/features/hire-a-boat-and-leave-the-land-behind