I did this swap early in COVID. 2000 t0 2003.
Maurice did a great write up. You should be able to find it in google. Search Maurice, Boxster, convertible top upgrade or similar.
If you pop the socket arms off, there is no reason to mark anything. But buy the sockets in advance. They often break and if you need to replace one, you had better have one on hand. And yes, you must mark or measure the location of the old one to make sure the new one goes in exactly the right spot. But if yours do not break, you do not need to mark anything. This is MUCH easier in warm locations as the plastic in cold can be brittle.
Get the plastic ones, they are meant to be sacrificial. They were really inexpensive at the time. The metal ones will ruin your top and clam shell if a cable snaps or the motors get out of alignment. And also take your time popping those off. They are on really tight. You will need a long bar to pop them on and off. I used a 4 ft breaker bar. A long screw driver will not work for instance.
You need two people to manipulate the tops, and lining up the mounting holes is a bit of an effort, but this is a very doable upgrade for a longish weekend afternoon. Assuming you plan ahead and have the plastic sockets in hand.
And BTW way, make sure you clear the speaker wires before you put the bolts in, or you will need to re-do the whole job. Ask me how I know. (Doh!)