Hey jersey
I dont know why you would use 2 washers unless the Nova plug was Long body and you wanted to de compress the Geo Dome C R
In future use Short body plug with 1 washer
DIDO
The fuel is what i recommend , i run in most motors like that with that fuel blend cos ive found it works nice. Castor is thick so it keeps things hot and it protects well when you have those tight tolerances in a new engine. If you cant be assed then just go to 25% nitro , should be fine, heaps of people do that.
Cheers <MM