@NinjaCyborg
Sorry but we don't find any email from you in our mailbox.
Using MOS and OS4 on the same HD is not easy. The only solution would be using the Parthenope boot loader.
You can find some information here :
http://elwoodb.free.fr/articles/Sam440/debian.htmlA simpler alternative is to install one of these OS on a SD card connected to the Sam460.
The other alternative is to use 2 different disks, one with OS4, one with MOS and you switch between them.
For the backplate can you send me a photo of the rear of the board? Just to be sure.
Send it to the email address I give you in PM.
Thanks