Delidding is very risky. I would personally not do so.
I got my dad the same CPU and a good air cooler like a Cryorig H5 Ultimate for $50USD or so should suffice. The motherboard must also support overclocking.
As per the "silicon lottery" who knows but 4.5GHz is probably easy to hit for many people.
Plenty of overclocking guides out there too. Just Google, maybe for your specific motherboard.
also run Memtest www.memtest86.com
and use your motherboard FAN SOFTWARE to setup a custom fan profile.
*Sustained temperature is recommended at roughly 75degC maximum (for optimal long life) though periodic spiking over this is fine. Use CPUID's HWMonitor, and use a program like HANDBRAKE (with TaskManager to monitor all four threads are near 100%) and test for at least 10 minutes near full load then tune the fan profile so it doesn't exceed 75 to 80degC.