I just did the thermal paste change and the results are very clear and satisfying for now.
Before: After 5 minutes on Prime 95 core 6 reached 93 degrees celsius, temp seemed to stabilize so I stopped the test;
After: 10 minutes of Prime 95 temps seemed to stabilize and core 6 (always the hotter) maxed 76 degrees celsius.
I'm probably not messing with this cooler anymore since the disassembly and assembly process was very tricky since most of the plastic parts of the cooler don't even exist anymore, so parts like coils and screws are not hold in place so it's very difficult to manage them, and even more because I didn't wanted to disassembly anything else except the cooler, so I did this while keeping the mainboard inside the case and GPU, memos, everything in place.
I recorded and posted on Youtube 2 videos, before and after, to show temps with CPU-Z, Realtemp and Prime 95. I don't know if it is againt the rules to share them here (my videos are not monetized), so if someone confirms it isn't, I will share.