Store technicians usually know whats up though. I am 100% bet that a good enough one could replace any part in a computer. Computers are merely components assembled together in a system that allows the maximum allowable compatibility between its parts. Thermal paste Ive heard is relatively simple yes, but not something Id consider ever doing due to... incidents in the past.

Which means that this is coming from a person with zero expertise in the matter, but much experience in having good technicians be able to fix anything. The only thing you should be impressed with me is my ability to know when to call it in.