definitely agree its not a good deal. ive seen cobra's in my area with 25k-35k miles go for 18k-20k. im probably having the same thoughts as you, supercharge the GT or buy a cobra. either way your gonna end up with the same #s, its just the thought of everything that would go with buying the cobra that makes me weigh my options.
kbb isn't accurate for cars like this. it doesn't take into account of how desired these cars are.. yeah you could probably do a tad better..
if i could go back and start over, i would have sold my GT and bought a cobra. way better platform to build on. you will regret it if you dump all that money into the gt when you could have had a cobra.. just think.. dump 10k into your car and make it badass, then it will still be only worth 10k