For Sure, can take a plastic garbage can and put in 10 gallons of 6% cleaning Vinegar, let the block down in with your cherry picker (as you have it nice and clean and de-greased already) until submerged, let soak overnight, pressure wash out the cooling jacket and block, rinse it off with distilled water and scrub it down with a scotch brite pad and some WD-40. Will look brand new and the WD-40 helps keep the rust back until you get time to build it. Cylinder bores can be lightly honed clean too after the rust is neutralized with the vinegar.
Did the same thing with a lightly rusted 360 Crank, made a fiberglass box the size of the crank. 4 gallons of 6% cleaning Vinegar, let soak overnight, rinse with distilled water, scrub with scotch brite pad and WD-40, polished up the journals with Crocus Cloth, Brand New !
This was a recently cut .010"/.010" crank, so yes sweet deal.
