Hello everyone! My dad gave me his old 1993 Chevy Z-71 Extended Cab & the rear speakers are no good. I think they are 4x6's. I saw some Sony Xplod speakers at Wal-Mart last night for like $30.00 & thought about getting them. It has some Polk speakers in the dash that work well & a old Sony CD player. Would these Sony Xplod's work well for the money? Whayt is all involved when replacing those 4x6 speakers?