A little advice from an engine builder's perspective:
See if there is an aftermarket flywheel from South Bend
or another reputable source like Centerforce that offers the correct balance, has the same ring gear spec, and offers the clutch pattern you need. Any time you change the balance on a flywheel without it being balanced with the crankshaft, you create a potential problem with vibration. That vibration may not be super evident in your application, but if it's there and goes unnoticed, you could wipe out the bearings or even break the crankshaft in that 7.3. An aftermarket flywheel will have the right balance (offset weight) to be within the oem range and let your project proceed without worry.
I've seen this kind of situation with gas engines literally hundreds of times, where the original engine is a different balance than the later engine and the guy gets the wrong flywheel or flexplate. Happens with small and big Chevrolet and Ford regularly these days. All it takes is a little research to know what the have and the issue is an easy fix, yours is potentially no different.
The Current Truck (Oct-2013 to Present):
1999 (Early) F-350 Lariat, CCLB, SRW, Black/Tan
7.3L Powerstroke, 4R100, 4x4, 3.73, 37x13.50-18s, '05 Axle Swap, 6" Fabtech lift, GTP38 "D66" turbo upgrade, SCT 4-position chip with custom tuning by me, Straight Piped 4" down pipe through 5" dual stacks, N-Fab full length triple steps, Pro-Tech cab guard and tool box, louvered 5th wheel gate, Hella 500 Fog and Driving lamps, much more to come...
The one I'll miss, (Mar-2009 to Jan-2014):
2000 Excursion XLT 4x4
6.8L V-10, 4R100, 4.30, 285/75-18, 271whp / 388wtq
The one I won't, (Jul-2005 to Sep-2012):
2005 F-350 XLT, CCLB, SRW, 4x4 FX4
6.0L PSD, ZF-6S650, 3.73, 35x12.5-18, 4.5" Lift