i replaced my bulkhead using my existing one as a template (I know you dont have one to use)...theres a good 6"+ from the top of it to the bottom side of the deck, but there isnt an access port like you have made.
I have heard 2 different sides to bulkheads.....someone told me to seal the bow off completely...make it air tight...so it floats if it sinks...then someone else said to leave a 1/4" to 1/2" inch gap between the deck and the top of bulkhead...this allows the bow to flex freely as glass and gel flex and wood doesnt.
Here is some pics of how i did mine....i basicly replaced what was there (from the factory)....since it was an early rogers, I am not sure if its the right or wrong way to do it, but it works.
two supports bolted to the deck then glassed to the floor....
then put in the bulkhead (it goes all the way down to the keel, but not sealed to allow water to escape) and butted the floor up to it.
