I have not used that particular grapple but I also have not had good luck with them (grapples). I have better luck with a standard Fortress/Hooker type and chain. Once on the wreck I make sure my anchor is set well before proceeding. I have in the past had a clip tied into the anchor line about ten feet above the chain to clip in with but I don't like that now. I just pick up my little 8 pound and wrap it around something. Course, you got to hit the wreck with the anchor or right by it. For bottom fishing I get down current and drop and for diving I often get up current and drop anchor. Don't know if that is right or wrong but it is what I have done.
I don't usually buy anchors, I just get all of the ones cut off and laying about, I have several dozen now assorted, some still with the price tag.
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