I did some internet research on how to melt lead. Igot a small coffee can, my propane torch and gathered up the scraps from drilling and trimming the counterweight earlier.
I then clamped a scrap of aluminum sheet on the bottom of the counterweight to cover the bottom of the holes.
I fired up the torch and melted down the lead (happens very quickly) and poured it into the miss-drilled holes.
I let it cool off some and then used a hack saw and round file to trim off the extra lead from the pour. Looks good.