Those generic spacers are HORRIBLE. There’s really no way to get them consistently centered because the hub bore is too big and the bolt holes aren’t round or the right size. So you always end up with wheel balance issues.
I’d be much more inclined to use something like this and have them drilled for 5x4”. The center bore is right, and you can drill the pattern for the 7/16” studs so even if the center bore isn’t perfect it should still sit centered on the studs