Have you looked in the H.sie options?
Those file names are for Stock. NYGM might use something different. The dat file is the 3D model, with nodes that are "linked" to the parameters in the sim file by the "Parent ID" listing at the top of a particular node's page. So if you open Sensors.sim with S3D, and look at the "12: Obj_snorkel" node, you'll see near the top of the page it's "ID: 0x9bbc018fa140ee32" and its "Parent ID: 0xac5f9baa2a26e0ce", which you'll not find the Parent ID in the sim file - at least, you shouldn't... But copy that Parent ID, open the Sensors.dat file, use "Edit", "Find", and paste that hex number Parent ID into the "Find what" box, press "Find next", and you should have "Node:170 - NSS_Uboattype7_SNK" highlighted (in Stock). Click on the "Model Preview" link, click the screen, zoom-in, and press the video camera icon just about the view window, and there's the snorkel and cover for the Type 7 centered in the window...
Download something like Notepad++, and use its "Search in files" function, and "target" *.sim files in the SH3 Data folder, including sub-folders. Use the submarine's eqp file to find the LinkName and use that for the search term. You can find all kinds of interesting stuff like that... Things like a snorkel or a gun are usually (not always) in the Library folder.
