I have handled dozens of engines with a home-brewed device that hooks under the rocker arm shafts just outboard of a couple of rocker shaft stands. Loosen the rocker adjusters, slide the rockers sideways against the springs, and lift directly on the shafts. No pain, no strain, no damage!
It's basically a clone of the factory fixture pictured above, which could also use the rocker shafts as a lift point. Those long eye bolts are still available, which were threaded in in place of a couple of head bolts but be sure to use ones made of forged steel, not cast or galvanized ones.
Jerry