You can use a couple of the rivets to hold it together and the rest can be fake or half rivets that are just solder in place. Rather than bucked over, a guy that had a g scale or larger model at NAMES a couple of years ago had just the heads of the rivet with a short shaft that was flush with the inside of the two layers of metal. Only one at the top, one in the middle and one at the bottom were real rivets the rest lookers as he called them.
His reasoning was he could get 3 or so rivets set correctly. But always screwed on up doing a line of rivets. His was a woods built vert boiler and donkey type engine for a logging set up.
You could tell that they were most lookers.