Hard Blok for 340 Stroker

i have never done that. but my idea is could you fill only the top 2-3". then drill the stock water holes? a not so interesting side note. back when i played with the chrysler 354 and 392 hemis. i saw an artical in a magazine that showed a guy that found that head on the 392 had spot above the ext port inside the head. that he drilled a hole in front of the head. that let him put a tube throu the head front to rear, and push water to cool the ext port.