adding raised sleeper to classics Optimus; how would you do it?

I thinking of constructing a "raised sleep with winds" on my classics Optimus, or rather Henkei Convoy, replacing the goofy looking wind vane and to cover the exposed head. Here are some
examples below:


Basically like the design Motormaster has. To you pros and experienced customizers out there - what method would you use to do it?
thank you

examples below:


Basically like the design Motormaster has. To you pros and experienced customizers out there - what method would you use to do it?
thank you


