Yeah the center bar doesn't really seem to be needed for support. There is bracing between the rad support and the center hood section. If I do remove the center bar, the one piece grill will be bolted around the entire perimeter of the resulting larger hole.

Was planning on using 1/4" or even 3/8" solid round stock for the entire frame and a few cross bars, and maybe 1/8" round for the vertical bars.