If you click the map image above it will provide you an easy to use Map of All Locked Toolboxes. The toolboxes contain various items from plans to scrap and ammo. You can also click this link to see the map too.
While searching you just might find the plan to create your own toolbox to display in your C.A.M.P. Here is an image of the stash boxes you can use. You might also want to check out the Locked Safes locations that are throughout the wasteland.
Where to find/farm Mega Sloth Locations in Fallout 76?
Where to find/farm Concrete in Fallout 76
What are the Lunchboxes for in Fallout 76?
Where to find/farm Rad Chicken Locations in Fallout 76?
List of Nuka World on Tour Tunnel of Love Plans & Weapons - Fallout 76
Where to find/farm Aluminum in Fallout 76
Where are the Nukashine Wake-up Locations?
Where to find/farm Radroach Locations in Fallout 76?