How to replace rear wheel ABS speed sensor on 2007 Saturn Vue

ABS and TC light came on. Had right side sensor replaced. Cost $250 at dealership. Now left side sensor gone out. I want to see if this is do-able for the novice. Anyone know the steps to replace this sensor?

Asked by for the 2007 Saturn Vue
very easy repair take off the drum and do not remove the brake shoes just loosen front shoe use a allen head to remove we get paid 20 minutes to change these under warranty
My brakes recently started making a horrible noise when I come to a complete stop. Not screetching. Feels like there is air or pressure build up when i push them in all the way. Replaced pads and still no help. Could this be the ABS motor or something?
Was it like a chattering noise or feel like sonething was rubbing against the splines of the drive shaft?