looking for final opinions before I send my 5.3 862 heads to the machine shop. I calculated at 61cc stock chamber I like to mill .040 so .007 to remove 1cc so I would be removing 6cc off chambers bringing my compression to 10.23.1 would this be correct? on factory .054 gaskets I will be running a low lift 216/220 .550/.550 lift cam should be ok on valve clearance