It works! I think I finally understood how this whole thing comes together and achieved exactly the configuration I wanted:     No synoinfo.conf modification is needed here. For this to work I had to set the boot config to include: DiskIdxMap=0C0005 SataPortMap=157       But HOW did I get these values What didn't make sense to me was how "maxdisks" (in synoinfo.conf, patched to 12 by Jun's loader), "SataPortMap", and "DiskIdxMap" play together