I am sure that they will look just fine with a 32nd scale P-51.
Here is a size comparison example for you. These are all IJA tanker figures. From left to right Tamiya, Miniart, and Verlinden. The first two look appropriate for an average Japanese male in the 1940s. The Verlinden figure is just a bit too big in my view. As soon as he was assembled, I decided to use a different Miniart figure.
F is for FIRE, That burns down the whole town!
U is for URANIUM... BOMBS!
N is for NO SURVIVORS...
- Plankton
LSM