My first removal was from a 30" by 30" x 8' brick column. If you really want to take it apart, cut the mortar and remove the stones if you can and start from the top down. In the column I removed, I started at the top expecting to have bees at least half way down the column if not all the way since it was over 3 years old. We quickly found out different. Brick layers get paid by the brick so they took all of the extra bricks and filled the column in. Yea, it is cheating but it really paid off for the owners because the used them to rebuild the column.
The stones are taken apart from the top, layer by layer, they will release easier.