Improving Dreamcast air circulation
Looking at the Dreamcast cabinet, I found that its configuration does not favor air circulation efficiently in order to remove hot air. There is an air inlet at the rear and an outlet in the side, however next to the source there is a plastic barrier that creates a dead end tunnel making it difficult for air to circulate there.
As a solution to favor the drag of hot air to the cooler I chose to create an opening in the back of this plastic wall. With a pair of scissors, I made a new fit in this plastic to allow it to be placed further ahead and leave an opening for air circulation at the back of the power supply.
In the next photo is the final result. It is important not to use Dreamcast with the lid open if you are not using a GDEMU 3D printed that blocks this top opening left by GDROM as the cooler will be less efficient by pulling more air from outside than inside the case.
Using a 3D print will further help divert the air to push the hot air column out of the power supply aisle.
That was the way I found to cool Dreamcast, taking advantage of my experiences with old PC cases, I think removing components is not the way. In my case I clearly felt the least warm cabinet after this change, and you still have to consider that I live in Brazil and it's getting hellish here.
I used Google Translate, I hope you understand.