That "period" word is what I like from BlackST

@ netwalker, having access to clean room is not "the solution". This model combined with this kind of situation is a difficult task to do. Opening up drives' cover is easy, swapping headstack is easy, UNLESS that drive is WD

(quoted from a post by Odiferous, as i recall) when unknown anomalies joined the fun....errrr....the task

DR pro even don't like to deal with this kind of damaged WD drives.
Spindle might not 100% K.O, unstable in my opinion. The possibility of platter misalignment after being dropped is the problem. Since this is high density drive from WD, a small drop can cause a major damage to its original condition. And, honestly, I hate myself when doing this "exhausting" alignment against WD

If you never do this, just don't DIY. Send the drive to DR pro near your place.