The bolts you have removed retain the entire steering cylinder to the axle housing.
Chances are, it has rusted itself in the housing & will be quite a challenge to remove.
I would try to unscrew the gland marked below (using a hook spanner) to get the rod & piston out of the cylinder. Remove the seals on each side, clean, install new seals, refit gland.
There are full instructions to do this on page 1 of this post - with the entire cylinder out of the axle housing on a bench.
![580K 4wd steering gland.png 580K 4wd steering gland.png](https://www.heavyequipmentforums.com/data/attachments/297/297457-9ea0f0f55432d9f8cc7845abc4ce3481.jpg)