instead of an adapter for the CM-6 i would get the correct plug cap for the plug you have. price is pretty much the same either way but the larger plug is more durable and less prone to fouling and the cap will be more reliable as well.

here's some plugs that will work:
http://www.gsparkplug.com/shop/spark...12&resistor=65

http://www.gsparkplug.com/shop/spark...30&resistor=65

the ones with Y or P in the part number have projected tips and might not work in your small engine.

also notice that the champion brand (denso as well) has a 8.3mm reach while the NGKs have a 9.5mm reach...in reality they are the same, NGK measures from the top of the taper seat while the others measure from the bottom...