I prefer to leave the the rind on, and eat it together with the rest of the bacon, but if you want to remove it, I'd do so before smoking. The rest of the bacon will get a smokier taste because of the area that is exposed to smoke.
I'ts not difficult to remove, using a sharp, but not too sharp knife. If the knife is razor sharp, so it cuts the rind like butter, it is better to use a duller knive, where you can angle the blade against the rind and make the blade follow the rind as you cut it away. It only takes a few seconds with some practise.