First of all you need to find out what is the real problem with your drive. You have to be 100% sure that you diagnosed the hard drive correctly. And serial port (so-called “Terminal”) is the only “proper” way to diagnose the hard drive. Forget about swapping heads until you are absolutely sure they are the problem. There is no room for mistake.
There are lots of reasons why a hard drive can make clicking noise, and yes, the most common reason is malfunctioning head stack (either a head itself or the preamplifier chip that is located on the head stack). But there are chances that the problem is not the head stack. You need to find that out via hard drive’s serial port.
Again, never open a drive unless you are 100% sure that the problem is inside. This applies to everyone, including all data recovery people out there.
Now, speaking about heads, it is possible to change the head stack without damaging platters. Cool guys somehow manage to swap 14+ heads head stacks without it being something very special to them. You just need some good experience. I believe it’s been told hundreds of times, but it is worth repeating: good data recovery people spent years to gain the knowledge and experience needed to perform something that is slightly more than just swapping PCBs and using Winhex.
Hope this will give you some better understanding of the situation.
