Not specifically devoted to schematics or drawings, but manuals used to include those types of resources and they’re relatively easy to find:<p><a href="http://bitsavers.org/" rel="nofollow noreferrer">http://bitsavers.org/</a><p><a href="https://archive.org/details/computermanuals" rel="nofollow noreferrer">https://archive.org/details/computermanuals</a><p><a href="http://www.retroarchive.org/" rel="nofollow noreferrer">http://www.retroarchive.org/</a><p><a href="https://vintageapple.org/" rel="nofollow noreferrer">https://vintageapple.org/</a>