1) Easy as pie or
2) A PITA ending with battered sights and a marked up slide.
And I can't tell you which it will be with any given gun or sights.
There are tools that make the job easier (check Brownells) but you may not want to go to the expense for a one-off job. If you choose to just go for it, get a good brass punch of the right size, a medium hammer, a good solid vise with copper jaws, and drive the sights out from left to right, in from right to left. Good luck!
Jim