[The Fixer]

You can do that, but if it needs any machinework done, why bother? The machineshop should hot tank the block and install new freezeout plugs/cam bearings for you. Then all you have to do is paint it.

If you're just re-using the bottom end as is, then clean and scrape the goo off the outside (stiff wire brush with engine degreaser), mask it, and paint it. Spray some WD40 or motor oil down on the cylinder walls to avoid rust buildup, and put it inside a large plastic bag until you're ready to build it.