If you use the glass mash between the hull and bulkhead, you'll be creating a hard spot which could cause a failure of the hull laminate and/or print through. Leave a gap between the bulkhead and the hull of a 1/2 inch or more. Use glass cloth to tab it to the hull. If you are careful, that will seal the bulkhead. If you are going to install a hatch
in the bulkhead, tab it on both sides.
You should make provisions to ventilate and drain the forepeak/chain locker so it doesn't turn into a rot/mold paradise or stay full of water from probably leaks
T&G doesn't have good strength in all axis. Use plywood
for the bulkhead.
Don't think a water tight bulkhead in the bow is all that useful. Most boats sink from rudder
damage, shaft log failures, and side glances off of hard objects. If you truly want to make the boat unsinkable or at least have a chance of surviving a collision
at sea, best to make a water tight bulkhead at the V berth bulkhead and another to seal off the engine
room and aft end of the boat. Have fun doing it cause it will be a PITA to accomplish.