It is not too bad to remove the motherboard. I have had far more challenges with a HP PeeCee and some other laptop brands which I do not recall at the moment. I am able to pull it in a few minutes now.

At least in this model the GPU is a large black ceramic package, not a CPU style visible die type of package (Like the newer nVidia chips), so maybe that is why the heatgun method does not work that good because the ceramic absorbs much of the heat?