I have a copy of Friendly Mission, Robinson basically did the south coast track and then walked up the west coast with a detour to the Arthur ranges, there is a map in the book that Plomley drew, based upon his notes.
@ mechanic Al - he was aided mainly by Tasmanian Aborigines (one of whom was Truganini) but, yes, he also had the support of a resupply vessel and some convicts.
he did meet a few of the West Coast people and they were not pleased to see him.
Addit: if you give me some time I can post some notes from the text to answer the OPs question or give me their email and I can answer it directly. If they are really interested the book is available from the QVMAG museum bookshop or Astrolabe bookshop in Salamanca. Anyway, here is an essay by Cassandra Pybus (linked below that describes some of the journey:
https://www.utas.edu.au/news/2017/10/30 ... pocalypse/