So I couldn't let today pass without making some progress. I figured I'd spend some time on the base, the boring bit. I wanted to tidy up the board that sits underneath the seat base. It's exposed so I needed to cover it.
Slot cut on each end for T Molding:

I then applied some of my DIY laminate to each end using blackboard vinyl:

The T molding was then fitted:

This was then screwed back onto the frame:

I also worked on the side panels of the base, beveling some of the edges, cutting a slot in case I wanted to use T Molding there too and also applying some vinyl inside and out:
