If you are filing 1116 and 2555, it sounds like your client is a US Citizen or US Resident Alien, right?

Yes, the income and expenses are reported on Schedule C.  The reduction of income tax is on the 2555 and 1116.

If your client is exempt from Self Employment tax because the he pays Social Security to Austraila and the Totalization Agreement says he is only subject to Australian Social Security, I'm not sure if ProSeries is set up to do that and I just looked and couldn't find a way.  If it isn't, you might need to do things manually and paper-file the return. As for what the tax return should show for that, see the links below.

https://www.irs.gov/pub/irs-utl/2019ntf-30.pdf#page=17

https://www.irs.gov/instructions/i1040sse#en_US_2022_publink24334pd0e305