I checked a lab system and it shows that ESXi 6.5 was available in SCOS07.01.12 and above. If you have a "dark site", meaning you have no external connections you can call in to support and request to perform an upgrade using the Storage Center Upgrade Utility (SCUU). This will allow your system to download, and upgrade in a non-service effecting upgrade just like if it were connected to our support servers.
1. There is a much more rescent Custom ISO for the 6.5u2: VMware-VMvisor-Installer-6.5.0.update02-10719125.x86_64-DellEMC_Customized-A07.iso
2. There is a tech document that says that configuring a SC which use SAS directly with the DSM Client is not supportet. (For us its works). You should configure the Array via DSM Datacollector(formaly known as Enterprise Manager).
3. I dont think that the SC makes a huge different between 6.0 or 6.5 Host types
4. Most importat. Please Read and understand: https://www.dell.com/support/article/us/en/19/how11081/preparing-vmware-esxi-hosts-to-attach-to-scv2...
5. I always take a look to the best practices guide and apply the adv. settings manually to the host