Hi @chrismack123,
Welcome to the Bunnings Workshop community, it is fantastic to have you with us.
Can I trouble you to upload some photos of the door, specifically the track system and the rollers, if there is any way to see them?
I'd say there's a good chance that the cavity door is a Hume Evolution Flush Jamb Door Cavity Unit. This how to install a cavity unit video shows the adjustment spanner being used at 4:40 and the timber pelmet being installed at 5:00.
Looking at the opening with the pelmet removed, it seems like you'd be able to use a standard shifter, but if not, we could certainly look at ordering an adjustment spanner for you.
Step 1, however, is to remove the pelmet. This will need to be done regardless of what spanner is used, so I'd start by looking at how the pelmet is attached.
If you can upload some photos, I could certainly take a look and see what needs to be done to remove it.
Let me know what you find.
Jacob
