sfperson

iTrader: (2)

I'm new to the forums, and I recently bought an '04 is300. I'm trying to switch out the radio, to a sony mexn5000bt, but i heard if you do, you lose some function of the speakers. is this true? also, i bought the metra harness, is that supposed to retain the full function of all the speakers and the amp? i am trying to install it myself. will it be hard? what tools will i need to install it by myself? please help. thanks