Non lead weights are horrible. They weigh less so they are longer which throws the balance off even more. The clip ons are real bad, they are huge. I bring all my wheels in for balance and or mount loose, because shops strip studs and don't torque with a wrench. I clean the backs of the wheels completely. I go to one local shop that uses real lead strip weights. They get it right on. Not a big deal on small car tires, but a huge deal on mud tires. Depending on the balance machine, some weights should go on the outer rim, some on the inner, some in the direct center, which I mark by determining wheel width, divide by 2, measure in, and mark it for them. Sometimes you have to compromise if that area isn't flat.
When I worked in a shop as a kid, I would spin the bare wheel with valve stem in place. If the wheel was off, I would weld a nut towards the center or inner edge, where ever the machine showed, and spin till it was true, grind or add weld. This was on steel wheels. Then you need much less weights. Old cast aluminum wheels you could die grind material to get them true. Also on Mud trucks I would weld on a tube over where the valve stem goes to prevent ripping the stem off, then weld a nut opposite of it inside the wheel to get neutral balance.
You want dynamic high speed balancing, this shows exactly where the weight needs to go. Also the backspace should be measured and entered into the machine. Most shops just set a default at 4 inches.