The following images show dimensions and placement for the helm on an ELCO 80' PT boat. These dimensional images represent a best effort on my part with the resources available to me. Please confirm dimensions given here for yourself if you have any doubts or if errors cannot be tolerated. Images are for non-commercial personal use only, please obtain permission for any other use.

Depicted is a 103 class helm although from what I can tell they looked the same throughout wartime production. I did see one image that showed what looked like a lever in place of the rudder angle indicator, not sure if it was an earlier/later version of the angle indicator, wheel lock, or what. See the image below, the spinning wheel pic is from Hollywood so beware. I included it because it's a good shot of behind the hub normally blocked by the spokes, and the parts look right. The gap above the upper wheel box flange and the console edge looks a bit large, and on other images I have the two small pilot light buttons on the console are at the top instead of the bottom. Also, the plans didn't always agree in minor ways like the depth of the steering wheel box at which point images were used to estimate. As usual, feel free to help. Let me know any errors and added details would be very welcome.

The wheel took an interesting route to the rudders. Based on a drawing in the book Allied Coastal Forces, chains, gears, and shafts were used. The steering went from the wheel at bulkhead 33 down to a gear box under the bridge deck via chain. From the gear box it made a right angle to the port via a shaft to another gear box almost to the sheer of the deck. Then it hit another gear box and went back, making an angle once to follow the decks edge, via shafts, bearing blocks, and universals to the stern side of bulkhead 61. A rear view shows it towards the port about right between the 2 outboard port muffler exits. At this point it is still just under the deck. A chain went from this point straight down along bulkhead 61 to a gear box about halfway to the chine. It then made about a 45 degree turn inwards and down via a shaft to the steerings gemmer gear located behind frame 61. The gemmer gear's output shaft was to the port about in line with the port rudder and a foot or two above the hull bottom. An arm on the gemmer gear and control rod turned the port rudder which was connected to the other two. Needless to say, the book's drawing is way less confusing.