I really don't think so. I know that people have turned them into mini fuges for a SW
setup, but I don't think that would benifit a FW
setup. I really can't think of anything in the HOB
that would be worth salvaging.
If you leave the HOB
alone, it would give you a fall back filter system just in case the DIY canister doesn't work out. If you take it apart, and still have problems, you then don't have a backup. It may be worth it to just leave them alone until you are sure the canister works.... just clean them really well before putting them up.