If you have done something like this before and you are sure you will not damage your console, sure.
I remember I modded an OG Xbox back in the days.
Personally I don't use my ps4 more then 2 maybe 3 days a month but I have a launch model and in some games, like uncharted and the witcher, it sounds like a freaking airplane.
I don't know how bad the pro is but If I had to listen to my vacation jet taking off every day I would proberbly just buy a new slim model, anyway since you want the "pro" extra's there is proberbly no way to get a silent one from Sony so you have to do the work yourself.
You could also wait untill the Xbox Scorpio is unvealed, you can say alot about the design of the Xbox (altough the S is amazing) but that console has been quiet like a cat sneaking around your house, and if the re-designed premium console doesn't make a lot of noise you could use that to play most third party games.
Thats my 2 cents, if you do decide to put it in a pc case make sure to share some pictures I would love to see the results!
Twitter @CyberMalistix
