Upgrade rear speakers

[bimmerman11]

I have a 91` 325i and its only got 5 1/4 speakers in the rear deck. i would like to put 6 1/2 speakers in. is it possbible i would like to know. thanx.

 

[bm528]

Does anyone know how to get to the rear speakers in a 5-series. I want to replace them myself, is this a easy DIY?