http://www.mcmaster-carr.com Part #s
5909K35 - (you need 2) theses are the bearings
5909K48 - (you need 4) theses are the washers
they install the same way the ground control bearings do
SIDE NOTE: I told someone else via email a bad part number - i told you one size lower by accident (long story on why)... anyhow get theses ones, they are only about 7$ shipped to your door