Chainplate bulkhead separating
I had a somewhat similar problem in my Islander 32, but instead of a portion of the bulkhead separating, the chainplate had pulled up and elongated the holes in the bulkhead. I cut a piece of 1/2" marine grade plywood to fit on the forward side of the bulkhead (which, in the 32, is inside of a cabinet). I then epoxied it to the bulkhead and tabbed it to the hull as best I could. I then filled the elongated holes with epoxy. After curing, I redrilled the holes and reinstalled the chainplate. You can't tell there has been a repair until you look inside the cabinet.
I did not need to pull the mast on my 32. I simply secured the two shrouds to my toerail with no problems. I was on the hard at the time so I did not have to worry about boat wakes, etc.
In looking at a picture of the port bulkhead on a 34 on the Yachtworld website it might be possible to effect the repair as I did. If the bulkhead around the chainplate is actually separating I would consider cutting out the bad section, inserting a same sized piece of marine plywood and then putting another larger piece of ply on the forward side of the bulkhead if possible. Of course, the asthetics of the repair are important and it may just be cleaner/easier to replace the entire bulkhead.
I could send you a couple of pictures of my repair if you think that would help.
Let us all know how the repair turns out.