If youre sweating the interior molding and stuff you shouldnt. If youre gonna be that extensive with modding it out itd be relatively simple to mod something similiar to what the newer Mustang convertables look like in the back seat.
Itll be a pain in the ass to mold it and get it the way you want it to look, but it can definetly be done, and done well.
Youll have to set up a few new screw holes though, but if you guys are good enough with the metal work to make it a 2 door then I really dont think youll have a problem with anything other then making the interior panel.
What I would do is use the smalles, but usable, bucket seats you can find for the back seat, mount them in the back to see what kind of room you have, mock up the size for the center console (maybe put a single sub for when it comes up to that hole in the back seat
) and see what kind of room you have after that. With that done youll be able to maybe use plexiglass or sheets of plastic if your not into bondo. Shape it so that the panels go behind the seats for a more cleaner look, and throw some screws in that part, then when it wraps around to the side from the back throw some screws near where the door seal would have been and end that piece.
To cover the rest of the side/door panel Id use a seperate piece this way itll be easily removed if you ever need to get at it. If you wanted you could even just remove the roll down windows and keep it with something that flips out like vans and SUVs have, or just like a real 2-door make the rear window just for show. The bonus with that is that you could probably throw another 2 speakers in each door to added sound if youre an audiophile.
Its all really easy to do when I explain it like that, but I can almost gurantee that once you get down to doing it and get in the groove itll go a lot smoother. Especially if you and youre friend have the right tools, imagination and time and patience to be able to mold and get it to look the way you want it.
For the center console in the back you could always throw a TV in it with videogames and crap, or even have a seperate audio system control in the back altogether. Make it sort of like a mini-SUV.
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