Hi Mustang and Welcome aboard!
1/48 huh? B I G !!! lots of details! First of all congrats for the great progress achieved so far.
Trying to answer your question: do you mean the torpedo-loading hatch (forward torpedo hatch) or the hatch separating the forward compartment and the previous one containing the officers accomodations, CO's cabin, radio room etc?
let me/us know asap
Cheers
SG