RE: DL-50 engine
You don't need to ground it to the head. The plug wire is already grounded. Make sure you have the cap all the way onto the plug, it is very hard to push on. You should not be able to see any of the hex around the base of the plug if it is on all the way. I haven't heard of anyone changing out Rcexl ignitions for another brand. They are very good units and very inexpensive to replace. A 4.8 volt battery is more than enough. Do not use 5 cell batteries.....