Thanks for getting in touch! I have had a couple of customers asking about TopShelf recently. I did some looking around for more information and can only find the following blog post.
(It involves using a custom script)
We do have a section on TopShelf down the bottom of our Windows Services documentation page (It sounds like you have already seen it.)
Apart from these two options, it does not look like there are any easier ways I have seen to install TopShelf services.