The challenge I have found for replacing hollow body frog skirts is that most of the replacement skirts offered (either pre-made of bulk skirt material) are way too short as they are designed for spinner baits and jigs . While the bulk skirt material comes in 5" pads , I believe you really need a 7" to 8" bulk skirt pad length to get started as essentially you are folding it in half once you insert the skirt into the frog ... Anyone with  experience in replacing frog skirts know where to find longer bulk skirt pads ??

http://www.jannsnetcraft.com/skirt-making-material/036620300008.aspx#FullDescription

Thanks !! I am familiar with the company but did not know of this product . The one foot length is ideal ...