Putting the computer stuff in the current livingroom would offer more space and improved cooling: there is more air volume (including a cathedral ceiling to absorb the really hot air) and the windows are sheltered by the deck overhang and there is no concern about rain coming in except in a major, major storm.
The livingroom only has two functions: I watch TV in there for a couple hours two nights a week when I do movie and anime nights (online), and guests sleep on the couch. TV watching would not be affected by the smaller room and it would make a better guest room in an enclosed and closable area.
Ordinarily I would just do it, except that I have been enjoying good relations with my mother lately and this would cause a certain amount of friction. Most of her would-be directives lately have been things I didn't care about, and it was just as easy to do it her way, or pretend to, and avoid a hassle. My mother has never fully grasped the nature of my my life; part of this can be explained by saying that she is the one who taught me by example that you can't really be an adult until you're boring (which is sad, because she wasn't boring when she was young) and right now she is essentially killing time until she dies, reading, watching TV, doing crossword puzzles.
The flip side of all that is that she is usually more understanding than I expect her to be. She says stuff and I ignore it and it all works out in the end. And this is something important, something that will literally affect my daily life and how much I enjoy it.
Maybe on Sunday I'll get a chance to do the measuring and see how I can make it work.