I have been making a few stick baits with an empty weight hole in the nose to be filled later on the water. I secure the weights with craftsmart plastilina clay from Michael's. I have a couple other baits that have had the clay in them for a couple seasons. This clay doesn't dry out and it secures disc-shaped lead pretty well. Saltwater doesn't seem to degrade it. The clay can be picked out of the hole with a hook and a new weight added then the clay repacked and made flush with the body of the bait.
I think if I were looking to make something that had to suspend perfectly and had to make adjustments on the water I would do this. Then could finalize it later.