heater cores at the bottom in the center of where the all the vac and actuators are, there are layers of stuff on top of it, your looking at a back breaking weekend, pull the console and the front seats, it will make life easier for sure.
and there is a bolt where the tubes to the core exit the car at the fire wall from the inside, make sure to remove that or the core may break on you. its on driver side of the inside of the car. at least it was on my regal, it cant be that different. a 1/4 drive nut driver for small sockets and and extension for it will make life easier too. and a good light.
