G'day
Bell Man. I'm not involved in FCL and have not kept up with all the changes since the Civil Aviation Rules came into force last year. However, I can tell you that you won't ever get a SCPL here again. It'll have to be an ATPL.
So far as I'm aware, if you've got a current licence from somewhere else, can meet the PNG medical requirements, you should only have to do the ATPL Air Law exam and the IFR exam.
You should find more information on the rules, exams and sample exam questions on
the Aviation Safety Regulation Directorate website. Many parts of the site are still under construction, but you should find some of the information that you need in the references to CAR Part 61, including ACs in that series.
Hope this helps.