Took 2 hours of work on one tonight with hand tools.
High-tech tools needed.....
Hacksaw (2 blades, MB is softer than pin but still ate first blade)
large file
small file
small screwdriver
pick
masking tape
3x5 card
pliers
Use a piece of 3x5 card and masking tape to protect BBL from slipping file and/or hacksaw from digging into finnish on BBL (first scuff taught me to cover BBL)
Use hack saw to chop off excess MB, there is a 1/4 inch gap from end of muzzle to where the MB thickens up again on the inside. I used 2 cuts to make sure I didnt hit the BBL, One to get most of it off by guestimating where the end of BBL was, got it about 3/8 of an ince from it, was still in the thick part of MB though.
Once you have excess chopped off take a hand file (large one) and file off the paint/blueing/whatever it is coated in off the bottom.
You will see a pin on the bottom of the MB (underside)
I used a hacksaw to cut slices down the side of the pin, the pin is much harder steel than the MB so the hacksaw just follows down the pin. Make like 6 slices into the MB and be carefull not to slice the threading below. Use large file to help remove MB material by holding it in a 45deg fashion to help remove material and widening out the cuts from the hacksaw.
Once you get close to the threads use a micro screwdriver or pick to start peeling back the MB material where it is thinnest, if too thick use hacksaw/file again.
Use a strong thin pick to pry the pin from the rest of the MB.
You have now worked up a sweat, go get a beer or soda now.
Try to slice the MB lengthwise with hacksaw and pick out metal where thinnest, make 2 of these cuts to relieve pressure from MB holding around threads.
At this point use pliers and unthread MB from end of BBL.
You will see century has drilled a hole almost through BBL for pin to fit in.and you will need to file down some metal where the pin went into BBL as it is rough and higher than the surrounding material.
Throw the PC useless MB into trash, you will hear loud clank as the MB has some weight to it.
It took me 2 hours since I tried to analize this operation too much untill I saw my hacksaw looking sad and not being used, shouldnt take more than an hour.
Good luck