Park Tool Tap Pedal

Do these have tiny hole in a back to use a spring loaded guide when using a drill press?

is the 9/16 tap returnable?

Could i use this tool to tap a hole i plan to drill in a deore xt or xtr crank? someone suggested that xtrs are hollow cranks so it would not work.

What size drill bit should i use if i am drilling new holes on a crank to make it shorter before i use this tool? this is custom project for a kid.