I do the same thing. When you do this, it can be a bit tricky depending on how big a hole you can afford to make in the fuse. I normally push the lead shots in first, then use a 10cc syringe to inject 60-min epoxy thru the same hole. You may need to drill another vent hole for air to escape when you inject the epoxy in. I use 60-min to allow ample time for the epoxy to flow in between the lead ball spaces. Clean any excess epoxy with alcohol and re-cover with monokote.