Sometimes, disk 2 can stay as is because it's only disk 1 that has to be cracked.
So just up disk 1 ... I'd like to take a look at it. Someone else might remember this version and say, "WAIT, I do know I've got the second disk somewhere..."
Moreover, in TOSEC, you often find versions that "only" have disk 1 available, most probably because disk 2 is identical to another disk 2 from a different crack...