Well, I am guessing that the bulkhead is structural... it has to be if the chainplates are TIED TO IT. If the bulkhead isn't structural, they would never have tied the chainplates to it.
Again, it would help if you said what kind of boat you had, since there may be a known fix for the boat that other owners have come up with.
The bulkhead attaches to the molded interior via screws at the bottom and screws to a headboard that is not glassed in, it runs to the other bulkhead and connects with screws. The headboard is kinda just wedged in and screwed to the bulkheads. I already said that most of the glassing wasn't stuck to the bulkhead like not glassed on(not done by the manufacturer). Ive been sailing it like that for a year on the bay, some times in heavy winds with no reefs. so basically the only thing keeping the rig up was bulkheads attached with screws being pulled tight against the cabin top. When you said the bulkhead needs to be replaced before i can use the boat did you mean that the bulkhead does more the hold the chainplate? because i pretty much explained that its not glassed in at all. When I un-stepped the mast both bulkheads and headboard could be move back and forth freely by definition(permanently fixed) It is NOT STRUCTURAL.
and originally(from the manufacturer) the chainplates were attached to the cabin top but someone beefed up the rig and decided to bolt new chainplates to the bulkheads, so you really jumped the gun on your I know everything and your a greenhorn speech, just because i just signed up on sailnet doesn't mean i don't know stem from stern only that i haven't owned a computer in a few years!!!