I don't know if you will remove the old CPU from your mobo, but just in case ...
To remove the old CPU, I suggest that you pull the HSF straight up.. well, perpendicular to the motherboard... because the CPU will likely stick to the HSF and get out of the socket. by pulling straigth, you won't bend pins and the cpu will be reusable.
to remove the CPU from the HSF, use a thin knife and pry the CPU off. I suggest that you put something, like the cushion that will come with your new CPU to prevent damaging the pin during this operation. Because I guess that the new CPU will be installed already in the socket.. Instructions come with the CPU to install..