Yeah, I will add a barrel jack later on my new Famicom case. This one is not the best looking work.
I still got 3 Famicoms around to bleach and mod. I broke not needed pieces out with a pench tool which doesn't look nice I should buy a Dremel or similar for better results.

Regarding the fan, I haven't encountered any issues thus far. My RPi is nice and cool inside the Famicom.