The mag disconnect (I don't consider it a "safety") is pretty easy to remove, and there are instructions in a number of places on the web. Here's a description that I captured some time back, and it was good enough to get it out of mine.
1) Remove the magazine and UNLOAD the gun!
2) Remove the slide from the frame.
3) On the right side of the frame is a pin holding the trigger assembly in the frame. Drive out this trigger pin from right to left. Use a starting punch to loosen it, as it is in tightly on most Hi-Powers and without a starting punch you'll damage the pin (been there, bought starting punches. [G]). It helps to put a piece of plastic electrical tape over the pin and surrounding area to protect finish. If tape wears or cuts, use new piece. I put a couple layers on the frame myself.
4) Remove the trigger assembly downward into the trigger guard while pushing in on shoe of magazine disconnect (MD), which is the flat, square, spring-loaded piece sticking into the magazine well. (You can tip the trigger lever (the lever on the trigger asssembly that rises up along the right inside of the frame, as viewed from the rear) rearward and slip it off the trigger assembly first if you like. This isn't mandatory but makes trigger assembly removal easier. Less stuff to fit through a small space.)
5) Once the trigger assembly is out of the gun, drive the MD pin, which is in the bottom of the trigger body just above and to the rear of the finger surface, out from the trigger body. NOTE: hold the MD in during this as it is under spring tension! Once the pin is out remove the MD and its spring from the rear of the trigger.
You can replace the MD pin if you like, but I suggest that you DO NOT. While it may not stay in and you don't want to lose it, more importantly, a Hi-Power with an empty pin hole in the trigger body is recognized by people familiar with Hi-Powers as an indication that no magazine disconnect is in place in that gun. It's a small thing, but might prevent an accident when someone is being otherwise neglegent.
6) Reassemble the pistol in reverse order, minus the MD.