Sorry, Bill, email was down for 2 days, a speed upgrade that went bad.
I'm still a bit confuzzulled because I have a small brain. I take it as 2 questions:
1 - aft the the torps there are grids of hols. These are on the Cod, and I'm not sure what other boats, I have to grab some research to get you more info. AS for the bottom, there are heaps and heaps of Kingston valves and similar in another style, but I don't have any info on grills. I will look into both of these and see what I can come up with, apologies for delay, I know it is frustrating! have a great holiday.