So sorry for taking so long.
I wish I could say I was so buzy that I couldn't get to it, buuuuuuut, truth is I simply forgot about it, sooooo sorry.
Here is what I thought of for the head.
If you want any changes let me know and I will make them so other people can build a working engine at the end.
I was thinking that maybe there might need to be a small boss on top to give the sparkplug more thread
I will post the rest of the parts I have changed within this week.