Two ways of getting shot of the mag safety:

1. Replace mainspring housing with after-market version. Or,

2. Take out existing mainspring housing - pop out pin at rear base of frame. Remove mag safety bar and spring, refit housing and pin.

In both cases watch out for the flat spring that controls the trigger/grip safety, if it pops out of place it can take a little fiddling to re-seat properly and ensure hammer strut goes into the spring plunger in the MSH properly.

If all goes smoothly 5 minutes work, say 15 to 20 if the flat spring needs shuffling.