Flash rust removal?

I have a nice freshly machined 360 that was on the stand covered. Over the weekend a water line going to my washer burst and sprayed hot steam and water for 2 days. I was out of town when it happened.

Pulled the cover off of my block and it is flash rusted. Bores are clean but a lot of surfaces are covered with a fine reddish powder. Sucks... oh well.

What is the best way to clean the block? I really dont want to have to hot tank it again and rehone the cylinders. Is there a spray and pray product? WD-40 and a brillo pad? What is the best way to get this block ready for assembly.

My new crank and hung pistons and rods are coming in next week so I would like to get it done.

This engine has been a nightmare. With being bored .060 over, needing a cylinder sleeved, a bent rod and a getting a new crank..... this is just another obstacle!

Oh well.... better then a crate block... right? ;D