HI Theo, Tom Lockley here. Yes, landplanes can certainly join in for as little or as much as they like. Goble and McIntyre had a seplane only, so they were unable to use land airports. This meant that they had to moor their aircraft each night, and storms and tides were a huge problem: sometimes they got very little sleep, specially in NW WA where tides are extreme. I would be surporised if many seplane-only aircraft took part, for this reason.
Anthony Coleiro is preparing a pilot's handbook and it will describe light aircraft lading and accommodation facilities near the sites used by G & M. The idea is that the anphibians might land in the original spot used by G & M then fly to the land base overnight.
Can somebody with a land-based plane join this tour?