Hi Carol, not sure what happened to your post - it ended up on the wrong thread.
You might find it useful to read the post I did on my water tank issues. It will give you a good idea of the structure of the tank. I think the “fibreglass bulkhead” you refer to is probably the first of the baffles - on my boat there are three - with the outlet fitting beyond them all. On my boat accessing that fitting from the tank side would be nigh on impossible without major surgery.