Key thing here is you need to do some hard defining of what sanctioning body racing you plan on getting to before you just start unloading all your parts. HPDE, track days and time trial types of racing are much looser with rules, if they even have any. Where rules do exist, such as NASA time trials, the type and level of the modification will alter your classification, so they still aren't particularly tight.

If you are considering sanctioned racing in a door to door environment, then you can throw away all vestiges of having a street car and simply build it as a racer. In that case, it may actually be easier and money ahead to pick up a Dynacorn Challenger shell and build it to what ever spec you chosen organization has rather than sell off, modify, and cut up your current car.

Pro touring maybe pretend race cars, but they are still a long, long way from being real race cars. The range of diversity between the different sanctioning bodies and their differing classes means there really is no one size fits all set up you can easily pursue. You will need to pick one, maybe two, and go after it.

As pointed out earlier in this thread, spending time at the track, talking to the guys in your chosen class before you start selling off parts and making your changes is the first order of business.