I knew exactly what the problem was and could not find sp_change_users_login, so I read the answers to decide which tried to do the same thing and got it correct. To me the value of the question is to educate that the old way we did it is going away.

And as for making the SID identical, well, yeah, this would be the IDEAL way to do it but in the real world, you won't always be administering servers you yourself set up if you get my drift. Always need to know your options.