03 mustang price info

Ok, i have a chev S10 that i am askin $13500 for and this guy may offer me his 03 Mustang GT for a strait up trade. I am wondering how much an 03 mustang is worth, as i would just sell it after the trade cause they do not intrest me, i would start another truck build up, is this a good trade?????? any info would be good, The mustang is in great shape, any ideas on book values for an 03 GT