i'd keep it a GT that is very classy
i would NOT do a serious tear-down. that will put you back a few years. keep her going. build a replacement small block in your garage & keep workin the body in your spare time. that way you can keep driving her enjoying her and make progress all along.
too many times i've seen guys pull them down, then never get them back together and eventually the wife makes them sell so they dont have a mess all over the garage. ;)