A4000D cooling

[A6000]

I have recently acquired an amiga 4000D, and can see that overheating could be likely, so I am thinking of attaching a fan on the outside of the case on the left hand side, so air is blown into the zorro card space, this will require a large hole to be cut in the case.

Is anyone horrified that I could contemplate such an atrocity?

[A6000]

I did consider having a slot fan outside the case forcing air in through the ventilation holes in the rear panel, but I will probably drill holes in the side as suggested above, and fit a 120mm fan in the PSU.
Thanks for your help.