only on freshly machined surfaces can you get away with a good spray of copper coat on both sides.
Then again what was used to clean the surfaces that could also cause an issue when trying to use the steel shim and some copper coat. You would have had to use some RTV around each water port on both sides if you didn't machine anything and then cross your fingers.
If you used too little rtv on the intake water cross overs "aka 4 corners" or the manifold is creating an A shape gap....it will leak into the engine. Front cover leaking is rare... but if the block was corroded around the water passages and not enough or any rtv was used, sure it will leak. Always rtv the threads of the long water pump/front cover bolts or they can weap around the head. Honestly I've seen worse have the oil changed and live a long life. Roll of the dice, your throw ..
