Sorry, no pix. Been years since I restored and sold (BIG mistake) my 30 CCPU but FWIW, here's what I remember.
Trucks use a different bracket than cars. One end bolts to the back of the light and the other to the underside of a wood block under the bed. There's also a wiring shield and a license bracket (on the left and same as car) that go on back of light - IIRC, license bracket goes on first, then tail light bracket, then shield. Reproductions of all parts are available - once you have them all, it's pretty easy to see how they go together. What I don't remember is how wood block attaches to bed - I THINK two carriage bolts go down through the steel bed subrail from the top, then through the block, then through the bracket.
Only the left light is original - dunno if a right was optional back in the day. Whatever, some folks put one on. Left and right assemblies are the same except left has the license bracket and a clear lens for the license light in the bottom of the tail light body. Although some put a left body and a license bracket on the right so they can display an antique plate, club plaque, whatever. On trucks, only the tail light door is bright - everything else is painted black.
Hope this helps.