Tom, This is from Sean (the guy with the 23 in Havasu). It's possible you might have both lead and steel punchings in your keel. Mine had a couple of lead ingots up in front but the majority was steel punchings. If I'm not mistaken, I think Theo Petron's 23 (which also had the same problem), had a combination. I think he had more lead than steel. If you dremeled into a lead ingot it would look shiny. Just a thought. I feel your pain! It kind of sucks when you are trying to figure out what the heck is going on and what you are going to do about it. I'm sure other folks on here will chime in with some advice. I can't tell you anything specific about the 15 as I haven't owned one. Keep the faith!!! Oh yes, my punchings were saturated in resin in some areas and not in others. One thing that was odd was that upon opening the cavity the punchings did not appear very rusty. About two or three days later after the cavity was drained and they had been exposed to air they were totaly covered in surface rust. Rust or not, you really want to get that moisture out of there. I've read a few places that chronic standing water on the inside of the hull can play a bigger part in blistering than the water outside the hull. Initially, before I became concerned about rust and swelling of the keel slot, I just thought I'd drain the cavity through a couple of small holes and pump compressed air through it for as long as it took to dry it out. Then plug the holes and be done with it. That was before I realized it was full of steel and not lead. After opening the cavity up I realized that I could have pumped air through there for a year! The punchings were packed so tight, and it was such a labrynth of resin mixed in with them that I don't think they would have ever dried out. I'd suggest that you hang tight for a couple of days and see what kind of advice you get from some other owners who have tackled this with an M15. If you can avoid the radical nature of the repair I've undertaken, I would. If not, be ready to get the wet stuff out and then let her dry out for as long as you can before you seal her back up again. I had Dauntless opened up for the better part of 4 or 5 months. Good luck buddy. If there is anything I can help you out with feel free to email me. Sean PS. I received advice from Theo Petron, Bob Eeg, Garry Oberbeck, and Jerry Montgomery himself. Without all that help I'd probably still be sitting in corner wondering what to do. The folks on this list are awesome and always ready to help.