About half way through my build and installing the spark plug. Have a grubee skyhawk 48 cc engine kit. Go to push the cap over the plug and it doesn't "snap" into place like a traditional plug connection that I'm used too. Looking closely at it, I don't think there is anyway that the head of the plug will fit into the receiver. I don't think it is supposed to just sit on top, but I think I'm missing something simple. Any help?