Sarel_ :
But one thing, does it have to be the exact same drives?
Same to the firmware revision.
And the WikiHow linked does not tell you that you
need a clean room and cannot allow any dust at all to get on the platters. If it does then the head will skip and can cause reading errors and possibly scratch the platters.
That is how a professional company recovers data
but they have the tools and a clean room to do the work in.