You can find the information you’re looking for by doing a search. Lots of threads out there about molds, modifying, opening hooks or using figure 8 links. The poison tail has what you are looking for if you want to modify. The aluminum molds can literally be modified with a hammer, I modify mine by starting with a hammer and refining with dremel. You can’t buy the coffin style from any tackle or component supplier, you might want to try an auction site.....
The other route is the D and M swim jig, you can open the eye and attach a blade very easily, comes out looking a lot like their old piranha bladed jig.
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