Metro convertible easy boat tail?

[hotrodfeguy]

I would think the last bow right above the window back to the tailight you have would be perfect by my naked eye.

[freebeard]

I'd say the second bow, the one at the back edge of the side windows.

The O.P. hasn't posted on this site since last June, but in case he's lurking: With a second header in hand it's a perfect opportunity for a Carson-style lift off padded top that replaces the top and deck lid. Electrical conduit frame with curved bows, chicken wire and then padding under the top material.

[hotrodfeguy]

Oh I like the conduit idea, can weld/tack it in place. Can also make for a teardrop shape like a rear of a vette.
This almost has me wanting to go out and get the top from a Metro CONVERT to make a Areo mod for my XFI MPG car I am looking into. I want to make a low CD car out of a spare XFI car I picked up. I have a goal of 75 MPG.