Is it possible? Yes.
Is it worth it? Maybe. Most likely no. But maybe.
The 7.3 will fit fine. The trans... I don't know. I've never read of anyone fitting a 4R100 into an OBS.
Just some things to think about though.
Drive shafts will have to be modified.
You'll have to goto an e-fuel setup.
Front suspension may need to be beefed up depending in if the OBS has a sb or not.
Plumbing and modifications for an intercooler.