When I was in high school most of us country boys, even us long haired country boys, drove pickups They all had a gun rack in the back. During the summer mine held a short fiberglass rod with a Zebco 33 on it and sometimes a 22 rifle. When dove season opened they were displaced by a Winchester 1400 and a Winchester 37 as a loaner. As When squirrel season opened the 22lr and an H&R Topper 20 gauge held top spots. Thanksgiving usually was the deer season opener and the squirrel artillery was replaced by the shotgun and sometimes a Winchester Model 92 rifle.
Back then it was a common sight to see twenty or more trucks in the school parking lot all sporting similar back window decorations. After Christmas there was generally a crowd before school to see who got a new shotgun or rifle from Santa.
AS times changed and it became necessary to lock your truck doors I removed the gun rack. When I bought a truck with an external gas tank the rack went behind the seat to store guns out of sight. Now You can't store anything in the truck you aren't afraid to lose. So, have set the stage; my truck gun is whatever my EDC is for that day or occasion.