My Vega, CITY ZOO, is a 1972 model, hull #1590. I want to use the lead and iron ballast in the keel for part of the SSB radio counterpoise ground. It will work if the lead and iron are solid castings. It will not work if the lead and iron are made of lead shot or punchings suspended in resin. So my question is: how was the vega ballast keel constructed?