You will either have to do “some surgery” or replace nearly everything, as @jofemodo already presented.
I am not sure what such a “surgery” can encompass, but considering the fact that nearly everything needs some modification, I am afraid it may not be as trivial…? Do not forget that Pi5 has ethernet and USB connectors swapped, so I suppose you will also need to cut the outer metal case - something I personally would be afraid of (since I always screw such things up with ugly cuts).