I would spend the extra $1 per plug to get them from the dealer, I bought 4 plugs from the dealer who was cleaned out then picked up the same model champion plug from an auto parts store. They were different plugs, the parts store ones had smaller electrodes and we almost a smaller plug. Sure suprised me, had to wait till the following week till the dealer got his next shipment, took the parts store plugs back, even showed the manager the difference.
I tend ot buy OEM dealer mainly because I KNOW it will fit..
When I did my rad hoses and heater hoses the same thing, the OEM one fit and were prebent so they, heater hoses, dropped into the same holders/clamps and the rad hoses came complete with the spring in the lower hose and the plastic wear guard..