Hello Brian.  I have a Gr. Gr. Grandfather William Maxwell.   Don't know where he was born but in 1875 on his marriage certificate he was living at 17 Rutherford St Belfast which is the Shankill area, he married Mary Graham who was living at 83 Hudson Street - also the Shankill   He was a stone cutter.  His father's name was John.  Do you think this is connected to your Maxwells.     Joyce