Sheet metal cylinders continue!

I would like to design Plenum Spigot which is fixed with cylindrical duct. As per picture below (ignore grooves, swages)

The cylindrical shape of that spigot needs to overlap to allow for spot welding, also we need a flange to connect circular duct with spigot. All I came up with is attached. Of course it has to be flatten after all to send it down to laser cutting machine.

Any ideas?