Navigator a-frame replacement????

[Guest]

We have a Hayward Navigator that we inherited when we bought our house. I noticed that it stopped moving properly. When I pulled the Nav or the bottom of the pool the feet moved fine, when on the bottom, the feet didn't move at all. I tipped it over (after removing it from the pool) and ball bearings came pouring out. I took it apart and 2 of the 4 little wheels on the a-frame have come apart and have dumped their bearings. I am trying to replace the a frame but I cannot figure out how to get the things off. can some one please tell me how to replace these?

Thanks in advance.
-K