Upgraded 2013 21.5" iMac and it is boots in under 30 seconds!

Meu Problema

Installed 16GB of Ram and 512GB SSD

Minha Solução

It went great, definitely take your time and keep track of where screws go

Meu Conselho

As I removed screws and did the steps, I kept the parts in zip lock bags together, which made putting it back together that much easier!