Never tried this but my mate who has a sheet metal business has this thing he calls a "nutsert gun" that puts nuts into a hole in just about anything like a rivet gun. I reckon that would definitely be the easy way. Some one else might know more about it.
I've used them before, I wouldn't do it unless its a last resort. You end up drilling a big hole, sometimes they go in well, often they don't.
The aviation industry has all kinds of cool rivets that are far stronger than the SS pop rivets we use. Other than availability and price, I am not sure why we don't see them more often.
