Trying to access your referenced website, I was confronted with:

Your connection is not secure.
The owner of ifixit.org has configured their website improperly. To protect your information from being stolen, Firefox has not connected to this website.
ifixit.org uses an invalid security certificate. The certificate is not trusted because the issuer certificate is unknown. The server might not be sending the appropriate intermediate certificates. An additional root certificate may need to be imported.

So, that's a no-go. How about a précis of the relevant info?

For that matter, why wouldn't a desktop iMac be worth it?