Grease 4 main wheel bearings and two nosewheel brearings using Aeroshell #5 grease. I have a bearing greaser that makes this job quite easy, but still very messy. Install the bearings on the main wheels and the nose wheel. The nosewheel bearings have a built in dust shield and seal of black rubber. I coated the perimeter of this seal were it contacts the aluminum wheel with grease. Next I inserted the greased bearings into the wheel then inserted the U-623-1 axle hubs into the bearings. Finally by compressing the U-623-1s as much as possible inserted the wheel into the nose fork (WD-630) of the plane. Centered the axle bolt hole and inserted the axle bolt and installed the washers and nut.