Was likely installed with the car on a lift which causes the frame to flex and the subs didn't line up. Cut it off, place the car on its wheels and try to install again.
I could see ditching the car if you just hated having a convertible or if a grail car fell in your lap but selling at a loss to build up a 2nd gen rx7...the maths just don't work. Would be cheaper to pay someone else to install a new top for you.