Just in case anybody is in the market for a tensioner, This Rennen Rollenlager is a very nicely made tensioner. I was able to make mine work by beveling the outside edge of the roller on my bench grinder. This gave me enough clearance to make it work. As far as the chainline I used it anyways and with 1/2" chain free play you cannot even notice. FWIW I would highly recommend this tensioner to anyone looking to use a vertical drop out frame for SS. Much more solid than my Surly that it replaced.