Depending on the size of your F4U there are a couple of options you may want to consider for concealing the antenna.

1. Install a soda straw inside the fuselage and route the antenna through that to the outside

OR

2. Use a Hayes 18" loaded antenna with the soda straw inside the fuselage.

I use the Hayes on several of my scale planes with good results. Range checks show about a 10' loss of range between the Hayes and a full length antenna.