IFixit yes, that firm famous for dismantling the most diverse products and posting photos and comments on the internet today published a series of free manuals on maintaining iMacs and mini Macs.
Only 241 in total, covering every type of component of Mac models produced from 2004 to c. They bring detailed disassembly guides, model identification, problem solving techniques and, of course, a lot of information about upgrades.
The cool thing is that all the guides are very well illustrated, with the quality photos we are used to from iFixit. It is worth checking.
