RE: What would work the best?
It's the same for us here frequency wise Bill. Way back when we followed suit with the US.
hello123, how much flying experience do you have? This is not a beginner's project you're talking about and that mention of the car radio makes me think you're trying to adapt something that may not be adequite for airplane flying. The radios from cheap ready to run cars do not have the radio range to work with an airplane. Some more detail on what you plan on using for a radio would help us steer you in the right direction.
The best way to do this is with aileron and elevator with throttle control being a very nice addition. Don't bother with rudder only for the reasons that Bill said and the fact that rudder only really needs some serious comfort level to fly as you need to keep ahead of the model mentally and plan the path with a bit more skill.
But to make these fly and take the structural loads there needs to be a lot of mods that can add weight if not done carefullly. And at that size wing making it heavy will mean an almost certain crash or at least a nasty model to fly.
To make this work you'll really want to have some of the very light parkflyer radio gear and a small airborne battery pack. Total weight should probably be no more than 16 oz at the absolute tops. But this assumes that you've flown models before. Otherwise I would suggest a trainer first.
PS: was that P40 at 300 gms with the radio and engine in it and ready to fly? If so then you're not that bad at keeping these models light. But that does not change the fact that you would be better off with a trainer as your first model.