my model years had a steal I-Beam that was encapsulated in fiberglass. The vertical web of the I-beam was rusted through on the front side. It the only thing of concern is the cracks in the surface of the structure, I don't know if I would have any concern. You could drill into it to see if there is moiture or rot. If you leave it, I would grind out the crack and fill it in to eliminate moisture getting into it. Mine was failing and allowing the compression post to rotate and tilt forward causing the ceiling of the cabin to indent on the front of where the compression post contacted the ceiling and the cabin top was starting to lower due to the compression post not being plumb. It was very hard to see except for the ceiling indent like the compression post was digging into it. The design didn't align the compression post with the mast step. It really had minimal support to the front half of the step. I added the second compression post to support this. It took a long time to figure it all out with the door but I'm very happy with it. The new structure that replaced the I-Beam is laminated composite counter top material with all-thread running vertically down into a bed of thickened epoxy I laid up the structure into then epoxy was poured into the holes for the all-thread locking the structure to the rest of the hull.
