Dump that junk stock spark plug and get an NGK 5944 BPR7HIX Iridium spark plug.
https://www.ngk.com/product.aspx?zpid=9496
They come pre-gapped with a protective cover over the bottom for shipping. Don't mess with it, it's prefect.
I put one of these in every new build.
That way I know any ignition problem is NOT the plug, and depending on your engine choices, it may last you 2 or even 3 engines.