Those large chin spin jigs are all I have for poured in. On my small jigs I use spring collar and switch blades as I want. With these I fish plastic as I have no idea how I would use feathers. If I want feathers or marabou I use pony head jigs and tie my own. What I like about the spring collar is I can change tail and blade very quick and get back to fishing. Here is the mold I modified. Hope this helps you with your mods.