I have a 1978 O'day27, the deck where the lower shrouds are attached seem to be a week point. When the rig is powered up, the deck looks like it is pulling up. The area where the Upper shroud is attached (where it is connected to the bulkhead) looks normal or not being stressed. I thought there may be a rotted core but it doesn't look to be the case. I've seen other boats that have stress cracks at the cabin and deck in those areas, mine does not have that yet but I don't want it to start crazing either. I was wondering if anyone has eliminated the lowers and used the upper chainplate to connect the lower shroud. I assume this will require changing the connection at the spreader and maybe strengthening the chainplate at the bulkhead. If anyone has done this, I was wondering what would keep the rig from pumping fore and aft, or any other info that would be of importance. I guess I could also keep the original lowers in place and install the 3rd lower which would really be strong. Any thoughts would be highly appreciated.