Why not contributing the guides on ifixit and just keeping local copies? You can at least save a pdf copy?

How often will your internet go out? You could also cosnider an archiving solution for visited pages. Archivebox comes to mind.

Will it work to find content on Lemmy easily by adding “Lemmy” to your Google query at the end?

Content is the second step I think…in my opinion copy what you deem useful und unproblematic?