I’ve used Hue Thief in the past. Usually works pretty well.

Bend the end of a zip tie into a U shape roughly the size of hole spacing and try feed it in one hole and out another.

Did you also put thermal paste between the slug and the case?

Might turn into a Streetlamp Le Moose situation.

I found an old 3u server chassis and put a regular atx motherboard power supply in it. 4 noctua 80mm fans and it’s relatively quiet for a server.

You can change the support top layer settings and mess with if there is top layers and how many there are, then adjust the gap between support top layer and the first layer of the print on top of it until it’s supported correctly and comes away easily.