your input please

Well fellow gear heads, I am calling on you all for help. In the near future I will be fiscally positioned to complete a project. I'm now just trying to decide what project it should be. As some of you know, my 88 thunderbird was rear ended a few months ago. The smooshed rear-end has made me take stock of what might be a overzealous love for an average car. For the past five or so years this car has been my toy, my daily driver, and my prized possession. I've won and lost races, gotten decent gas mileage, and dumped a poor man’s fortune in to it. Now I have a chance to either take it as far as It can go, or start with something new. This is where my mind gets clouded. I know there are faster cars (a lot of them) and I know there’s easier way to go fast, but the history is there with the tbird, so it’s hard for me to decide.
That’s why I'm asking for help, please show me some unbiased views to consider.

Here are the cars I'm considering:
Fixing the old 4banger tbird
4 door fairmont sleeper with my 2.3t, or a v8
2 door fairmont sleeper with the same
82 nissan 300z with a chevy 350ci and a 150shot(actual car available to me.)
64 thunderbird hard top
maybe another fox mustang?

So tell me what you think.