I am attempting to draw a tank similar to the design of the box attached.

The tank will be much bigger and will need to be created from four separate sheet metal part sides as they will all be different in design at the tank base.

In the box drawing attached I have used the "Closed corner" sheet metal command to create a small gap between the mitred corners of the top angled flange.

Is there a method of creating a similar corner in an assembly of sheet metal components.

I have attempted to assemble two folded sheet metal sections overlapping at the corner and then "cut extrude" using the sheet face but this creates varied results because of the normal cut needed for the sheet metal part.