Hi

I have a 2012 Kia Sorento diesel 4 cyl 2.2L D4HB engine, with odometer 676,000 km. 

I recently found out that very likely one of my fuel injectors is dirty or clogged, after a very bad batch of fuel.

I emptied the tank and refilled, and also replaced fuel filter. 

After doing lots of investigation, I suspected timing chain, and eventually found it was actually clogged injector due to that bad batch of fuel from few weeks ago. 

I believe it is a piezo electric fuel injector. 

I used fuel injector cleaner in my fuel tank and it helped a bit, but was only a remedy. Didn't fully fix the issue. 

I am planning to buy 2nd hand set of 4 fuel injectors from eBay car wreckers, and I'll confirm with them about compatible fit. 

I saw this video on YouTube:

https://youtu.be/m48DOynrDSg?si=1BMinvTl2s5hr7Xx

And I'm obviously planning to do this replacing by myself. 

Does any expert mechanic on this forum have anything to suggest? 

I'm a little bit paranoid that I might damage the fuel injectors if not done correctly. Does anyone have any suggestions to be careful of when removing fuel injectors? These are piezo electric and I watched a video about how sensitive they are and can be damaged. 

Is there something I should be careful of? Or any recommendations?

Can these be unclogged somehow without replacing?