This may not be of help, but on my H33 (1982) there was a long plywoot plank that was held in place with SS piano hinges the full length of the settee, with lots of screws, just like ggrizzaed stated; It folded over and it then sat on top of the 2 lazarettes (or whatever you call them); It was supported by a Mickey Mouse little bracket between the drawers at the front, and another similar bracket attached to the back of the galley sink
I removed it, because it was all ugly, but I may re-install it again one day, using a bracket fitted in the middle that folds to the side, just like the one fro ggrizzard
By the way, there is a Hunter 30 in the salvage yard I go to, with many good parts
I hope my posting be of help, I myself am beeing helped by some of the good people of this setup
Jorge