It's fairly safe to just do it yourself. Simply be aware you don't have to force anything too much. Pushing the ram into the slots is likely the most force you need. Even if you get something wrong as long as you didn't apply to much force and break some pins you can just reseat it and try again.
CPU is the one you're most likely to mess up but that takes virtually no force at all. If you're using basically any force, stop and turn it because you clearly don't have it lined up correctly. They should drop in and then lock into place.
If building it is of interest to someone I think anyone can do it. If you don't know, just stop a check a youtube video but these days it's fairly easy to do and virtually impossible to plug anything into the wrong spot.
I disagree. The Idaho stop is a very real law and it's been proven safe. There absolutely should be a different rule for cyclists and we already have decades of proof that it not only works but increases safety.
Also, pedestrians don't stop at stop signs currently. It's perfectly legal for them to continue without any kind of stop and I'm not aware of any place on earth that requires pedestrians to stop or has ever given a ticket for the them failing to stop.