[kk2002s]

I used the same parts that are in the kit, Pierburg composite pump, low temp thermostat.
This job is typically a preventative maintenance project so you would not be throwing money away replacing
Do a Coolant replace at the same time
Using a Vacuum fill tool will verify any leaks in the system
I've had a bad tank and old cap and did not get the temp issue you experienced.
So I would lean towards WP, thermo as possible culprits.
Once you get WP off, you may see broken vanes which could cause blockage and contribute to overheating.
Also important is to remove front bumper and clean radiators