Aircraft should be repaired only by competent mechanics but they should be looked after by their owners and operators; plus, there are situations in which any sort of technician may not be available, so every pilot should know what to do for expedient field repairs.
So, if the next mechanic is in a galaxy far away, what do you do with your mighty, albeit malfunctioning, bush plane in the middle of nowhere? Rules and regulations say that you have to bring the mechanic in, let him work and then get off with your airplane, but that is not always practical or feasible at all.
For example, if you have to abandon an area that is to be affected by an incoming fire and the only thing that you have is an aircraft with some sort of malfunction that is fixable, would you give up such a good chance of survival and run away because of some regulations written by people comfortably located in a cozy office? What of you have to evacuate someone that desperately needs medical attention?
Taking digital pictures before disassembling anything may help you reassemble the parts soon afterwads.
Please bear in mind that I am not suggesting you to break the law or act imprudently; the fundamental concept of aviation is safety and nobody could seriously pretend to do the job of a qualified technician or engineer just because "you saw" how maintenance and repair work takes place. Having said this, however, also consider that the cornerstone of this article is that under special circumstances you may be left with no other choice than to do the job yourself.
Safety comes first and if you have a choice always go for existing rules in the realm of aviation; stay the closest possible to them because unlike many laws written for common life and urban situations air safety regulations have been created by real professionals - not politicians - with security as a sincere goal. If you do make your own repairs always choose the path that will give you the highest degree of safety while staying as close as possible to the norm.