I'm looking ot put a roof rack on my car to hold my mountain bike. I have a 2003.5 and it doesn't have a roof rack. I looked at the rain gutter fillers and there are 4 small filler covers and underneath them there looks to be some sort of mounting bracket. Is there an aftermarket roof rack that bolts into this? Were these brackets meant for some sort of roof rack that Mazda is planning on coming out with? Thanks for the help.