A few points:
Silversides was a Mare Island built submarine. Boats built at Mare Island, Portsmouth and Cramp shipyard employed "government plans". The limber holes along the side were very different (rows of horizontal slots) from submarines using the Electric Boat plan set (EB and Manitowoc yards).
Government limber holes:
http://www.navsource.org/archives/08/0823204.jpgThe limber holes on EB plans were horizontal "D" shaped with the straight end at the bottom.
http://navsource.org/archives/08/218/0821721.jpgIn some cases, additional limber holes were later added to EB boats, most notable USS Gato herself:
original Gato limber holes:
http://navsource.org/archives/08/218/0821248.jpgand late war USS Gato:
http://www.navsource.org/archives/08/0821201.jpgDuring the war, the conning tower fairwater configurations, armament (guns, large & small, and gun locations) and radar, radio antenna outifttings changed constantly. Original Gatos had large enclosed conning tower fairwaters which were gradually cut down to reduce the silhouettes, especially at night. Subs began the war all black (Ms 9) and then had gray, black & white camo (Ms 32) schemes. Different subs had different configurations at different time points. The later Balao and Tench classes had very different and much smaller and open fairwater configurations.
Here's an early Gato conning tower:
http://www.navsource.org/archives/08/0821501.jpg and also seen here:
http://www.navsource.org/archives/08/0821601.jpgHere's a late war cut down Gato conning tower:
http://www.navsource.org/archives/08/0822415.jpgHere's a Balao class conning tower:
http://www.navsource.org/archives/08/0828742.jpg and also here:
http://www.navsource.org/archives/08/0830507.jpgThe best advice is 1.) pick a submarine 2.) pick a time frame for said submarine, 3.) find a photo of the particular sub at a particular point in time. Pay attention to the conning tower and the armament configurations. There is no generic Gato submarine. Your mileage may vary....