this is what I did for my Roo....

1) using a tap drill size for your screws...drill the mounting holes thru the jetcat mount and into the Roo.

2) Counter sink the holes in the Roo so that your screws are about 1/16" below flush.

3) in a piece of scrap hardwood drill and counter sink a hole for the screw you are using. dill size = major diameter of the screw. now c'sink the hole in the block that the screw is 3/64" below flush.

4a) place a spare mounting screw thru the mounting hole in the jetcat mount and into the hole you just made in the block of wood.

4b) place an old screw driver in the mounting screw, with a small hammer stike the screw, to drive it flush to ID of mount.

what you have done is extruded the holes in the mount. the scrap block of wood is the die and the screw is the punch.

5) check the screw to be flush to the inside of the mount, you may have to strike them again, or deepen the C'sink into the "dieblock". once your adjustments are good then extrude the other 3 holes.

6) check fit of mount to the Roo, you may have to deepen the C'sink into the Roo.

7) install the mount. done