I repair Cat 27 lead keel bolts. I have a problem with the aft pair of keel bolts . I drill and tap about 2 inches forward of the aft pair of keel bolts and am running into steel. This cause my lead threading tap fits and I wounder if any body know what is down there. I have asked Jerry at the factory and they don't seem to have any records of how the keel bolts were set up in the Keel. Between the forward pair of keel bolts and the aft set of keel bolts they cast in bricks in to the keel to displace lead. They are about 9 inches down. This causes me fits because I can't drill and tap as far down as I would like to. Hitting steal if also not good. If you have any information about were the keel bolts go under the lead I would sure like to hear form you. I do get one set of keel bolts drilled and taped in about 15" forward of the forward pair of keel bolts Don 310 4186481