Looks like if your GPU follows the reference design that this aftermarket unit would work. Might be worth contacting the vendor to verify, one way or the other. However, I think that since the HD6950/6970 are so new that you may need to wait a while for more alternatives.
That being said, how is your overall airflow in your system? Do you have the ability to install a side fan to blow cool air into the GPU/CPU area?
OK. Not too bad. Try downloading and installing hwmonitor (Google it and get the free version). You can use it to plot a temp history to see how it goes up and down over time. Regardless, I think you are okay for now. If you see large spikes over 85, then I would get a little concerned.
Still need to know what power supply you are using. Have fun!