center or offset washers for 76 dart with keyston classics by cragar

need to order some lug nuts and not sure if i need to order the offset washers or the center washers. 76 dart 4.5 bolt pattern. wheels fit fine but obv need to get em to stay put!!

also they all seem to be normal RH thread which people tell me seems weird? did y\they change to normal threads on all 4 wheels later on in production years, or maybe the PO swapped the studs?