harness question double neck yoke

I don’t know if its called a Double neck yoke, or twin neck yoke… in some pics I’ve been looking at kind of like a D ring. The harness I got with my team when I bought them was a nylon one had a martengale on it, this Harness I picked up is leather, has short tugs for logging and off the britchen there are two straps that run up through the pad part that goes over back with the belly strap and then there are two hooks, think its called a side backer or something like that. I didn’t know much about the harness and untill I put it on and took them out i didn’t know those straps were supposed to go on the neck yoke. My question now is I see some pics where the harness where the side backer strap is tight at all times and is on the yoke and there is a strap or chain that runs from the hame rings to the yoke and its just loose and weight isnt put on it at all I assume its only when stopped? I need help with knowing how high or low the yoke should be. I have the style that have a yoke per horse and then go to a neck yoke that mounts to the pole but I’ve seen them where they have just a single piece that the side backer straps mount to and that connects to the pole. If I have enough time I’ll post a few pics of what I’m talking about

Thanks for the help.