In this Bill Making Stuff video, Bill shows how he turned a box of native American warriors into a 10-person warband for the Stargrave sci-fi skirmish game. He chose these figures because they were nearly naked and allowed him to build a lot of armor plates and scavenged junk onto them.
He created a whole backstory for his warband. They're a group of post-apocalyptic scavengers called Rusters. These would also work great for the new Necromunda Ash Wastes game that was finally revealed this week at Adepticon. They'd also be perfect for Scrappers, an underappreciated post-apocalyptic skirmisher produced by Osprey Games (makers of Stargrave and Frostgrave). Or any other post-apocalyptic miniatures game.
As usual for Bill Making Stuff, there are lots of scratch-building, kitbashing, and general modeling tips in this video. He also runs through all of the basic tools you need to do this type of improvisational modeling.