Advice on Banjo uke, making slots bigger on bridge.

I got an old Banjo uke and every time I play it the g strings pops off. So I got a new grover bridge, The slots are not big enough. So I got a torch tip file set and want to make them bigger. Any advice on how deep I can go to ensure they don't pop out. I assume they have to be all the same depth as well.

I've done the same thing, just groove it out a little at a time, make sure the strings lay in the groove well, check the action and do it again if it needs it.

Thanks Mike, It worked great. Now I just have to lower the action.

I read that when you file the grooves down you should do it at an angle to make sure the highest part where the string rests is the side facing the neck. If you do it the other way it could maybe make a buzz from vibrating "inside" the bridge. Did that make any sense at all? Ill draw a picture if not.