I have an 1890 house and the attic floor has settled by about and inch and a half since it was built. However, the main chimney has not settled (or has risen by 1.5"?!?). The contractor put 2x6's around the chimney bricks and nailed the T&G to them. I removed the chimney a few years ago, and was left with a pronounced hump in floor around the where the chimney is located, since I did not remove the chimney further a brick lower than the attic floor. I assume I could take up the T&G and remove 3/4" from the 2x6's (6" side) that surround the chimney and renail the T&G back to mitigate the hump in the attic floor. The 2x6's that surround the brick are higher than the floor joists by about 3/4". Mainly worried that using a sawzall on the 2x6 around the chimney will mess with the lath and horsehair plaster that is attached to the bottom of the chimney surround. Anything else I might be missing? Comments?