mac 500

I have come across numerous Mac 500 & 600 PCBs in various conditions, many missing their part number sticker. So how do you tell which is which? Is there a noticeable difference? Thank you.

Hi all I'm having some issues with 4 old mac 500. I solved almost all the problems but there are still a few thiungs that keep coming back. 1rst: There are some motor drivers that keep blowing up. I keep replacing them for new ones but always blow sooner or later. I was suggested that it was...