what was the difference between the c10 base and custom in 1969?

[rally]

I'm trying to figure out what my truck started its life as. The SPID is missing from the glove box and the frame was cut down from a longbed, so I'll never get it back to what it used to be. But what I would like to do is get it back to looking like what it did at the start of its life.

I've done some searching and can't find definitive information saying what the difference was between a base c10 and a custom 10 in 1969. There's a Custom emblem on the glovebox, but it looks too good for it to be original (I could be wrong...). The fenders have Cheyenne Super badges and at least the grille and bumper are from a 71-72.

I know what the grille and bumper look like from a 1969, but as far as other options, such as chrome trim, accessories (there's a cargo light over the bed, which I heard might be something that had to be ordered specifically), I don't know what came with the custom that didn't come with the base.

Can anyone point me in the right direction so I can figure out what I have by process of elimination?