You have a couple of options:
1. have the thicker spacers(adapters) machined to make the center hole bigger
2. Get some shank nuts, but the wheels lug holes may not be big enough to allow a shank
3. find some different wheels with the correct wheel spacing
4. replace your studs with longer studs and use the cheap spacers and standard lug nuts
unfortunately, none of these options are cheap. I've found adapters cheapest on ebay.