Well the first thing you have to realize is that your going to be paying more money for the trade and more money on insurance. They both sound like nice cars, the hardest part would be finding a buyer for the GT. The GTP would be a nice upgrade, but you can get most of those upgrades for the GT. The interiors can be switched out fairly quickly and you can usually find a good deal. You can also do a topswap on the GT, basically taking the s/c pulleys/heads/lim/supercharger/vac lines from the GTP. There are writeups for this stuff in the how-to sections or do a search. I would just put the GT for sale and if anyone comes soon with the money you want, sell it. If the GTP gets sold in the meantime, keep the GT.
