1940 ford truck

Hi.
Does anyone know the dimensions on the filler panel that connects to the lower front of the 1940 ford pick-up bed? This is the 3 or 4 inch panel that fills the gap between bed and running board. I am having bedsides made and am not sure as to whether they should be 3 or 4 inches deeper to compensate.

Thanks,

Tristen

I don't have the dimensions but try www.northernclassictrucks.com They sell the extensions that I believe you are looking for at $25 a pair. I bought a complete bed from them several months ago and can say that the quality of their parts is very high.