I stopped at Advanced Auto this afternoon to get a replacement spark plug for my Sportsman ETX. The manual says it’s a Champion RG6YC. One of the plugs they told me was a cross reference was an NGK TR5. But I’m really confused. Trying to compare specs, the NGK says the thread body is 14mm. Another site says the Champion is also 14mm. But something else I found says the Champion thread body is 10mm. And nowhere that I found online shows the TR5 as a cross reference to the RG6YC. Any one with any thoughts?