I have multiple sheet metal parts that form a cylinder when put together. I need to add a hole pattern in each part around the cylinder.

If I create the holes on part1, then I can't pattern the holes around to the other parts in the assembly. I can create the holes in the assembly and pattern around. When I open the part to save as a dwg flat pattern, the holes from the assembly aren't in the part.

What is the correct way to accomplish this?