I have a 99 saleen speedster convertible, and ive noticed when i go over 50 mph i have a small rattle or flapping noise coming from what sounds like the rear right fenderwell area. ive checked the entire fenderwell on the outside and nothing is loose. i stuck my hand down under the convertible cover inside and couldnt feel anything flapping around. got any ideas what it could be? it doesnt sound like anything major, just a piece of plastic or something flapping. anybody ever had this happen?