Well.....While replacing my valve cover gaskets to fix oil leak I had to tweak the dip stick tube to get everything back together and SNAP. Dip stick tube broke off flush with the block. Any ideas on how to get the remaining tube out? I pulled the exhaust manifold to get better access. Was thinking maybe a bolt and slide hammer?

A tap will thread in better without expanding the tube in the bore(keep the vacuum cleaner running). Heli-Coil taps are off sizes if a regular tap doesn't fit quite right. Then the slide hammer.

Tap will work for sure, but you can also try an easy-out. It should twist out pretty easy. Use a wrench to get it tightened up and then a visegrip and pull as you twist. They normally come out pretty easy.

use the tap to tap the thread. DON'T slide hammer the tap. thread in a bolt. taps are hard...and brittle. bust off the tap and u gotta pull pan and hammer it out from below. another option look for a dipstick tube that adds on to oil drain fitting. 1/'2 13 thread.

A tap is going to displace metal and create shavings and small particles. I wouldn't do it even using a vacuum. Use an EZ out as Marc stated above.