Michael,
Doing some basic conversions and using the expanded dough calculating tool at
http://www.pizzamaking.com/expanded_calculator.html, and assuming that you are using the Morton's Kosher salt and that one cup of water weighs 8.2 ounces, I get the following:
Flour (100%): Water (78.8461%): IDY (0.91947%): Morton's Kosher Salt (2.2792%): Olive Oil (7.326%): Total (189.37077%):
 737.1 g  26 oz  1.63 lbs 581.17 g  20.5 oz  1.28 lbs 6.78 g  0.24 oz  0.01 lbs  2.25 tsp  0.75 tbsp 16.8 g  0.59 oz  0.04 lbs  3.5 tsp  1.17 tbsp 54 g  1.9 oz  0.12 lbs  12 tsp  4 tbsp 1395.85 g  49.24 oz  3.08 lbs  TF = N/A

Note: Assumes one cup of water weighs 8.2 oz.
From the above dough weight of 49.24 ounces (I used 49.236415), and with your 12" x 17" pan with a surface area of 204 sq. in., the thickness factor comes to 0.2413549.
If you plan on using the Diamond Crystal Kosher salt, then the dough formulation looks like this:
Flour (100%): Water (78.8461%): IDY (0.91947%): Diamond Crystal Kosher Salt (1.61443%): Olive Oil (7.326%): Total (188.706%):
 737.1 g  26 oz  1.63 lbs 581.17 g  20.5 oz  1.28 lbs 6.78 g  0.24 oz  0.01 lbs  2.25 tsp  0.75 tbsp 11.9 g  0.42 oz  0.03 lbs  3.5 tsp  1.17 tbsp 54 g  1.9 oz  0.12 lbs  12 tsp  4 tbsp 1390.95 g  49.06 oz  3.07 lbs  TF = N/A

Note: Assumes one cup of water weighs 8.2 oz.
With the above dough formulation, the corresponding thickness factor = 0.2405077.
Peter