Rim Jobbie is located in the Large Blade camp in Gutgash’s territory. Use your map to locate it, it is at the top right of Gutgash territory.
This is a video showing all of the History Relic, Scrotus Insignia, and Scrap Locations in the Mad Max Rim Jobbie Top Dog Camp mission. Completed 100% percent. Raw Steel paint job unlocked after boss fight.