Power steering valve body

That's the spool valve. There's no gasket there and do not attempt to use any sealants. It's nothing but an o-ring seal. There's also fore and aft adjustment to it. If it's not in the right position, there's a very good chance the wheels will slam to the left or right when you start the vehicle - so be careful. The bolts have to be just loose enough so you can tap it slightly forward or to the rear where the wheels will stay centered.

Study the section of the service manual I've attached. Note step 18.