venting a banjo rear end?

I am running a hot rod works open drive conversion on my 37 banjo and I know I hav eto vent it and I also know that this is a dumb question but, do I need to take the rearendoff the car and disassemble it prior to drilling to avoid any shavings getting in it or would it be okay if I drilled it in a step fashion (start really small and gradualy get bigger) with it left in place?
Thanks

 

Replace a bolt with Hotrodworks hollow bolt with vent

 

I tried the hollow bolt and it threw grease everywhere. Ended up drilling and tapping for 1/8" npt and used a screw-in vent at about 10:00 o'clock, 6" away from flange on left side; this keeps it away from the eggbeater action of the ring gear. Use a glob of heavy grease on your drillbit to catch the shavings, you'll be fine. Three years, no leaks.

 

I've got one from Hot rod works?? How did it throw grease out of that TINY hole? I like YOUR way.

 

You can buy magnetic drill bits from your tool guy.

 

We had mixed results with the "vented bolt". We recommend installing the vent outboard of the differential bearings.