Has he ever worn any clothes such as a t-shirt? If he tolerates light clothing he may accept a vest style harness. There are many vendors who create and sell light harnesses that are more like an article of clothing. Also you could try bringing him outside and then putting on a harness (get a friend to help) hopefully he will be so interested in the outdoors that it will distract him and he won't put up as much of a fight. Once he is able to explore he may forget about it. Good luck I am positive that you will find a solution
