Replace SAS 300Gb 15K of VRTX

Hi Dell expert !

I am using VRTX with 3 server blades. I created 3 group of RAID : group 1: 8ea x 300 GB 15K, group 2:6ea x 900 GB 10K, group 3 :9 ea x 1.2 TB 10K and all groups are RAID 5. Quorum disk was created on group 1. Now, the storage space of 3 groups disk near reach to limit and I plan to replace 8ea x 300Gb 15K SAS disks with 8 ea x 1.2 TB 10K disks. To do this task, I plan moving all data, Hyper-V host stored on group 1 to another group. After that I will shut down VRTX and replace these disk, plug in new disks and create RAID again. But I don't know these steps that I plan are right or not? How about Quorum disk will be created automatically or I have to do it by myself?

Please give me advise for my case? Thanks