I am a bit of an artist

I have been drawing several World War two aircraft and need some ideas for the P-51D Mustang, I have the Stars-and-Bars already in position, as well as the kill marks on the canopy. After I have several answers, I will make a poll for the final answer. I also need a scheme for a B-17G, I already have the Stars-and-Bars on the side as well. The final aircraft I am requesting ideas for is the Piper L-21B Seneca "L-Bird" Light Recon/Liason Aircraft that replaced the L-4 Grasshopper in Korea, all I have is the plane itself, no roundels, no branches, no numbers, no nothing.