I have done 2 blocks with hard block...Both were done the same way and I feel both worked very well..
1st block was a 396 for a Nova (stocker)
Bolted the main caps on and torqued them up
Filled 1 side of the motor and bolted a set of steel heads on...then we did the same to the other side
2nd motor was a 100 over BBC (S/ST)
did exactly the same thing...the only real difference was the 505 motor had head and main studs.
I think 1 over the most important things to remember is that the insides of the block have to be clean. I had both blocks sit in the hot tank solution at work over the weekend and then washed them out with hot soapy water, rinsed it out with the pressure washer and then put the motor in our bake oven and dried it out over night... Lastly just to be completely sure I sprayed the insides of the water passages with an electrical degreaser and contact cleaner.. I know it may sound excessive but I firgured if the metal was oil/grease and rust free I would have the best results.. I think I did