Hi!
The plug you should use is an OS 8 or a Enya 3! naturally there is other plugs to that works good but these two are the best sport plugs on the market
Old typ idlebar type glowplugs should not be used...they work okey too but idlebar plugs are not needed on modern engines...

Regrading fueltanks...never use just only a silicon fuel hose from the fuelpick-up inside the tank.....the hose will eventually bend forward in a hard landing.
Instead solder small piece of brass tubing to the fuel pick-up clunk and this "bending forward"action will not happen.

When enginetuning is concerned ....this is all done by ear! -This is how you tune engines!
Just listen how they sound and react accordingly.
If you dont know how to do this ...ask for help from someone who knows.

When you tune an engine which is sitting in an airplane its vital that you allways hold the models nose up for a couple of seconds (5-10seconds)! You don't have to shake the model at all....just hold it upwards and adjust the highspeed needle slightly rich.

Regards!
Jan K