Musky0503, I make a few bucktails and Slippery Sam's. One of the best items to tie body material to is flex cable like used for the linkage on lawn mower carbs. This allows the body to move a little on the wire shaft which goes through the flex cable. If you are needing a keel weight just take the size sinker you need, drill a hole through the side of it so the weight hangs down off the flex cable instead of running the wire through the original hole in the sinker. Crimp with pliers if needed.
With the Slippery Sam type lure, the problem is to keep the blades and metal parts from compressing into the rubber body. I drill a hole in the rubber body and insert a section of flex cable longer than the rubber body so I have something to tie my skirt to also. This way the lure body and skirt are just riding on the flex shaft, and the flex shaft, by being longer than the body and skirt, support all the weight of the blades and metal parts.
It takes more weight to keep big blades down in the water column than you first suspect so I recommend you buy solid metal beads to add extra weight to the front end. Good luck and let us know how it works out for you.