I would not suggest moving to a low wing war bird untill you have some experience on other planes
The P-51 while a good plane is not easy to fly, it requires fast flight all the time and doesn't like slow speeds at all
Most of the low wing planes are bad to tip stall when slowing down to land
I also am looking forward to getting a low wing war bird but not ready yet
if the electrafun is the plane on your profile and that is all you have flown as of now you definately are not ready for P-51
I would suggest a J-3 cub or maybe a cessna 182