While reaming out a crusty glow plug hole, I forced the tool
too much and 1/4 inch broke off the end and is stuck in the hole.

Do I need to pull the prechamber?

I don't have the removal tools so I was thinking of this:
I have a strong magnet I can put inside the prechamber
I was thinking of trying to force the end of the bit on through
and catching it with the magnet.

Your advice would be GREATLY appreciated!

Thanks,
Jeff