Missing Superblocks

Good-day All
I "have" an array RAID6 6drives 1 spare. The OS got corrupted on reboot.
On a fresh install the array is non detectable. Investigation shows that 
out of the 6 active drives only the first one has a valid super block 
the rest look to be corrupt. My assumption is that this might be down to 
the fact that I raided on raw drives /dev/sdX and not on partitions 
/dev/sdX1. Is this recoverable or should I load from a backup?
I assumed trying to create using --assume-clean should work but 
currently the only drive with a super block shows as busy except it is 
not mounted.
Many Thanks
John Atkins