A few updates from today.
There was no E clip keeping the catcher flap rod in place - another little piece of the puzzle missing. So that was easy to remove. Handles all removed, forgot to tap out the roll pin from the clutch lever, but that doesn't really matter.
Most the day was taken up degreasing the drive wheels.

Holy hell, that isn't something I want to do again. Three cans of degreaser later, a smidgen of petrol and I think that is the best I'm going to get them with what I have to hand without asking the environment to take another one for the team...
Deck came up pretty bloody well. A bit of degreaser on that and a brush and scrubbed. Pressure washed off. Still managed to keep the original "Press to Prime" sticker pretty well intact. As a bit of an amateur photographer, forgive me for taking before and after shots in different light.
Tyler - I really only wanted a VC160 or Mustang. But beggars can't be choosers. I have no need for SP, don't really want it but getting the gearbox and ancillary bits apart, cleaned and reassembled correctly will be a new challenge. Hopefully, it'll "preserve" it for a few more years too.