Well, you got the answers you were looking for, here is a different answer. To your other implied question, how to not worry about dust getting in other holes.
Main thing is to develop positive air pressure. You want more powered intake than powered exhaust.
Use fans for all your filtered air intakes, ignore powered air exhaust, run it at lower fan speeds if you can. Air will get out fine. If you force the air in where you want it to go in, dust will only go into the easily removable filters, it won’t be on your components. Any extra hole in the case will just be exhausting the already filtered air. Then just remember to actually check and clean your filters. That’s the hard part. But if you clean them when they need to be cleaned, you will never have to actually clean the inside or the fans or components or anything else, just the filters.
2019, back in #avocadotoast days. When apparently we wasted our money on extravagances like “not the cheapest fruit/vegetables”. Which wasn’t even the case. We literally didn’t even do that, we 100% had to eat the cheapest fruit/vegetable, if we were lucky enough that any fruit or vegetable met our budget. They were so out of touch that even their attempt to find a minor extravangance they thought we could afford to waste money on but shouldn’t, was inaccessible.