Putting head on slant six

Finally did it guys. Found myself a complete 72 swinger. Every piece is there from head to tail Virtually rust free. The guy I bought it from said the previous owner took the head off for some reason (thinks to replace head gasket). Car has been sitting in a car port for sometime so there funk in the cylinders and I want to know the best way to clean things out in the block before reassembling. Also any tips for re assembling the head (valves are still in head. Needs lifters and rockers out back in.). Any good threads anyone knows about or tips? Thanks!!

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