Either remove the muffler or loosen it up and rotate it as shown, then snug back down. Mark the spot to drill the mounting hole, which is 1/2 " in from the edge of the tip bead when installing the DBK-UK part number. Center punch as shown.
Wrap the muffler with masking tape to protect the outer surface, then drill the 1/8" pilot hole using the provided drill bit.
Now drill the 17/64" finished hole size using the provded drill bit. Rotate the muffler back to the proper position and re-tighten the clamps. De-burr the hole with a fine half round file, drum sander in hand drill or dremel.
Apply a light coat of white grease to the entire outer surface of the DB Killer and o-ring, then install lining up the threaded hole with the mounting hole in the tip. Note! The DB Killer is installed with o-ring facing out as shown. It can be aligned or removed using the provided allen wrench in one of the holes, pliers may be needed.
Install the allen bolt with lock washer being careful not to cross thread, then snug down with the provided allen wrench. Re-check the bolt after 100 miles of riding.