Since I started the thread I guess I could theoretically delete the entire thing, does that answer your first question. I just wanted you to have your own thread as this ones title is not drawing you the attention to your questions that you apparently are looking for. The title is about an M41 which is not as popular as WWII tanks. A new thread started by you indicating the type of WWII tank you have would be far more beneficial. Folks here love WWII tanks a bit more.

The ratio you are asking about has already been answered above, go back and re-read the thread. If you cannot figure it out from what has already been posted then you might be in the wrong hobby. R/C tanks are a bit more challenging then cars/trucks and you will have to problem solve on your own far more. Sorry but its the truth, there is not a lot of hand holding with tanks.