I agree that hub-centric spacers combined with longer wheel bolts can overcome this situation, but I would seriously question the cost-effectiveness of buying 4 hub centric spacers and 20 new lug bolts for this application.

I think that if the OP really wants 15" wheels, he can buy aftermarket 15's with the correct offset and which use the factory wheel bolts, as you suggested.

SteveM.

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