When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I would use the NGK TR6 spark plugs with a .35 gap. The -4 line is smaller than the -6 line. I would guess if it's for a 100 shot it's the -4. Good Luck..........