Hey Bro,
if you look in those side vents, they have screw posts at the very top, which line up with the side markers. but only line up if you switch them as jimmy said.
it was weird but does the job

 

I know what you mean.

 

Right, I got that part, I was more curious about what was used to actually fasten them in place? I can't remember how they were fastened to the stock bumper. It's been two years ago since I pulled them outta there lol.

 

ahh my bad Tim,
ok yeah they have these weird nuts in the back. ( lol sounds so bad)
that bite into the plastic posts of the side markers.
here is a pic from the last time i took them off

 

Ahh gotcha. Thanks a bunch! I noticed the marks in the plastic posts, I just couldn't remember what exactly was on there. I have a feeling I'm gonna have a hell of a time finding those back, haha.

 

Hey Tim,
I found these on Fleabay,
but couldnt find the exact ones for ours.
but i believe the name is the same, side marker nut or retaining nut.

http://www.ebay.com/itm/Mopar-Side-Marker-Nuts-1972-Up-A-B-C-E-Body-New/130390417530?_trksid=p2045573.m2042&_trkparms=aid%3D111000%26algo%3DREC.CURRENT%26ao%3D1%26asc%3D27%26meid%3D7195587965507592304%26pid%3D100033%26prg%3D1011%26rk%3D3%26sd%3D360637796503%26