Another Mike chimes in.
Sometimes slow and steady pressure works better than prying and sawing.
In the attached photo
you can see how Iíve positioned a few bar clamps to apply pressure in the direction I want the Lewmar
port to move.
Once you have the clamps in place slowly tighten them to increase the pressure. Wait a few minutes before tightening again. You can actually hear the caulk start to separate from the frame. Finally with the last tightening of the clamps the port pops free, undamaged and without pry marks.
The key is to take your time and not crank down on the clamps all at once. Tighten, and walk away for a few minutes.
Iíve used this technique on 4200, 101, Lifecaulk, silicone, and some other unidentified caulks.
Something to think about anyway.
works on 4200 as well as 5200.