Technical Stumped

Purchased a 51 chevy truck a few months ago. It was partially disassembled. I can't figure out where these two brackets go on the truck .
I have attached a picture of the parts.
Any help would be greatly appreciated!

 

Hang on BRB

 

Do they only fasten on one end? Better pictures would be good.

 

https://www.autometaldirect.com/bod...evy-gmc-short-bed-stepside-pickup-p-4769.html


https://www.ebay.com/itm/234657239338

 

Yep it holds the filler panel above the running board in place. That was an extended brb, fight my way though weeds, get one shot because the battery went dead, stop and fix the picket fence to keep the skunk out of the yard.

 

Thanks for the quick reply. This is my first fifties vehicle. Having fun with it. I am going to update my profile soon. Thanks again.