Can you date this panel?

[nyr208]

First, sorry if this is the wrong place or fourm.

The picture is one of the two painting trucks my family owned from sometime in the 60s to the mid 80s

My grandmother believes this one is original paint and the older one they used house paint to match this truck

So far this is the only picture I have and will be searching for more this weekend.

Can anyone tell me what year this panel is and if it is a factory color.

I'm hoping to find a project of the same year to make a replica family truck