Not sure what year this tailgate is off of

[Woz05]

I picked up this tailgate about a month ago and I'm not sure what I'm going to do with it yet but I atleast want to figure out if it is off of a specific year.

I don't see to many with this style letter stamping, I didn't know if it was ,maybe a 67/68 style only or something laong those lines.

Any help is appreciated.

Oh I threw a few extra pictures on there to show off how nice it is lol