How to sketch a weldment Dome

Having some difficulty in sketching a weldment dome - Framing is to be 2"x2"x1/4" angle Stainless arched on each end and conected thru the center.

Can not figure how to draw the scketch on the arches for the stainless to connect to each side on the angle to create another structual group.

Need to then wrap the top with 14gage stainless sheet 48" wide x 92" long.

I have attached a sld file and DWG file for reference.

Any help is appreciatted on this and I am using SW 2013.

Thank you,

-Scott

SolidworksWeldments