Ok first I'm not a spearfisherman although id love to try. I am an avid hook and line fisherman and i joined the forum solely to chime in on this thread. If you're not up to setting up a dermestid beetle colony and al that l Ive found that just hanging a head by some stout monofilament high enough from the ground to keep raccoons and other scavengers away and just letting the flies/maggots have their way with it works pretty well. They tend to stick to the softer flesh and leave the connective cartilage alone (Just check on it fairly regularly because once there is nothing else left they will start eating it) so you end up with the skull still articulated. just strip off any remaining skin and wash and maybe lightly bleach the skull (too high a bleach concentration will actually eat away at the bone) then set it in the sun for the cartilage to dry out solid like you would with a shark jaw and you should get a pretty good result without an inordinate amount of effort
