While the steering box is out...

If you have any type of leak from the oil filter housing mount, now's the time to replace the gasket. With the box out you have easy access to the bolts holding it in. Otherwise you need the cut-down allen key.

And have plenty of rags packed around the box while in transit. You'll think you've got all the fluid out, but you don't, and it'll find its way onto something important.