'48 5 window information

[48jim]

I just bought a '48 5 window cab and chassis. There is no engine or trans but the front and rear suspension are intact. The frame is remarkable and very solid. My ID tag on the door post reads 21FR-H 3668. Can anyone help me decipher the code? Also, the drivers side, side cowl door is missing and the open/close hardware, any idea where I can find replacements?

Thank you, Jim Williamson ([e-mail])