I'm curious what kind of harness Ruger has tried? I know when we got Tuffy, I got him one of the soft padded ones & it was awful for him! When I researched the whole issue through YT & other places I soon realized it was going to take some training with him no matter what kind of harness he wore (he's a puller too). When we go out for walks if he begins to pull we stop for a minute. If he can continue to walk after that without pulling we keep walking; if he pulls again, we immediately turn around & go the other direction (just for a few feet). At first it will feel like you're going to be going nowhere but it doesn't take many walks like this for most pups to learn.
Hope this helps a bit
By the way, I ordered a harness called Choke-free for Tuffy & another for Bella when we got her. If you'd like to see it take a browse through our album on my profile. here's the link
Pet Collars and Harnesses that do not choke dogs and cats