After a year of searching, I found a 1994 Honda Civic VX (49state) to base my project on so let the fun begin!
As the title suggests, I plan on using a solar system from
SunRNR.com to allow for the removal of charging system losses. This solar system is cool because it uses a 135Watt solar panel hooked to a small battery unit. The SunRNR unit has a built in 12VDC charge controller and power invertor to supply 120VAC.
Heavy gauge power cables will connect the rear mounted SunRNR battery pack in parallel to the stock car battery and electrical system. I anticipate that removing the alternator belt and charging losses will result in sufficient gain in MPG to quickly pay for the SunRNR unit and more.
The SunRNR solar panel has a very sturdy aluminum frame which reduces the chances of damaging the panel and should allow for easy integration into a boat tail addition. It looks like the best mount will use the existing upper rear hatch hinges to make the solar panel into a new hatch. I'll upgrade the hatch support struts to hold the extra weight which will make it a functional trunk lid. Initially I'll be building the boat tail out of foam for easy shaping and aerodynamic testing. The outside will then be clad in a skin of fiberglass or aluminum and the trunk will be hollowed out leaving a layer of foam which gets fiberglass. (EDIT: The solar panel fit better on the top of the car)