Clearing the port is not your concern. Your only requirement will be clearing the head with the piston dome. If it does that, don't go any further to try and space the cylinder losing compression and bumping the port timing. Dry fit the cylinder kit without the rings on the piston first and check for clearance.
Also, I am a DR guy too. Scored them, busted them, BENT A SKIRT.. fixed it up and kept on rolling. They are hard, good word for it. Also, they for certain require no spacing.(edited)