I've got an Aussie 2005 F250 7.3L Powerstroke which is the same as your 2003. Ford Aust kept planting the 7.3 into the 99-03 Style F250s until late 2005 as special RH Drive built trucks.
I've been running Toyo OPAT AT 305 70R 16 tyres and on 10" rims and have no rubbing problems. There is a very slight touch on the inside of the front mud flaps but nowhere else.
Aussie spec Brazilian built 2005 (US 2003) F-250 Superduty 4x4 7.3Ltr Powerstroke: Donaldson (AIS) Intake with Zoodad, AIH deleted, DIY CCV & catch can, 26” x 3½” Cummins straight through muffler, MBRP Black Tip, Foil Delete, Old Man Emu (OME) HD rear spring set, Front leveler spring, OME Nitrocharger Dual Tower shocks front, OME Nitrocharger shocks rear, Tough Dog Steering Damper, ARB Air Lockers Front & Rear, V10 Tranny cooler in series with Stock Tranny cooler, Deep Tranny Pan, Extra Cooling rear diff cover, ARB HD Front Diff cover, ARB Bull Bar, Kymar Dual Spare Wheel carrier & Rear bumper, Edge Evo with Dash Pod & EGT pyro, Long Range Fuel Tank, OEM Style paint matched wheel arch flares, VMS in Dash GPS Street & Off Road Navigator, Toyo OPAT AT 305 70R 16” on 10” Rims.