You're right o targaet in all your obersvations. basically, tho it's a good model, the Revell kit is of the post-war Cobia, because that's what they studied to make her.
Marker Buoy should be- like in war pix - a large round manhole covere with at least 4 circles of holes like the deck, and not sure what's in the ctr, the drawings indicate to large circles of something and the photos are unclear. The rectangle with oval ends marker is very post war.
And the diff yard boats have the diff companionway, as you say, EB = PORT buoy and STB companionway, and Portsmouth PORT buoy (further fwd).
Drilling out - I would also suggest using a ballcutter or similar ina dremel and drill out a bit form underneath, so that the holes give the illusion of being in thin metal. It might not make a difference, but the technique works well with big holes, like the vents in the VIIC uboat - I thinned the edges of mine to give illusion of scale thin.
The cross/keyhole you mention - a mystery, tho it is definitely a ost war add-on. If it were me, I'd go with some of the good photos out there and ignore the modern.
I am researching to release a metal deck replacement in Photo Etch, but I'm not sure how that project will go. In some ways Revell seems to have gotten it wrong, but overall, it's pretty good. There were so many variations.
That link to Fleet Drydock of the Sub Committee has the flood hole info, and it is a good resource in general for the Gato. I have also started a forum just for this model, about a year ago, over at:
http://p104.ezboard.com/brevellgatosub
Please keep us all posted on yoru reseach, thoughts, and progress!
Not sure how to post images on this forum, the FAQ wasn't all that helpful. If you head over to modelshipwrights, they have a gallery section, both for general and your own...
http://www.modelshipwrights.com/
Hope this helps, keep up the goo work
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