Put the grommet in place. The larger side goes downwards. I greased the grommet ring using bicycle grease, (OK with rubber & plastics). Push the speedo into the grommet up to the bezel. I made a tool by bending a small screwdriver blade to make a small 'L'. Keep the speedo lightly pressed down then use the tool to work around lifting the grommet rubber over the bezel ridge. Easy!