The construction of the PK floorboard can't be Piaggio's proudest moment. The sandwich construction will trap water and keep the floorboards under constant attack. If you have a look underneath, in the back of the floorboards, there is more or less a "trap" forcing water up into the construction.
Luckily, this PK was pretty rust free except for a hole on the right side. To prevent further rust attack a Hammerite "rust stop" was utilized on all seams. The stuff was also utilized underneath. Looks awful now, but the plastic on top will hide it.
