I managed to connect an old serverHD over an 68->50 adapter to an Oktagon 2008. Just works fine, while the onboard SCSI of my A3000 doesn`t like it.
I`d say it`s no Problem to have this kind of setup wehn you use a more modern SCSI-controller like all P5 Modells. I was asstouned that the Oktagon 2008 did take it, but maybe is was due to the latest ROM. Older controllers like the GVPs or Commodore modells (apart from the A4091) seem to have problems with those modern drives.
When it comes to properly terminateing those 8 high-bits some controllers are more forgiveing then others if you use just as simple 68->50 converter.
Just buy one of those 68 SCSI-drives and an adapter und try it with all of your SCSI-cortrollers to see where it works and where not. as you have a Blizzard 2060 you won`t buy it for nothing, as with this card it will work definetely.