My dad said glue the track to the felt, then remove the pins holding the felt and place aluminium bar down the side with slots in for the few fastenings needed to allow the felt to slide. which if my small bits don't work out then i will have a look at doing as the. The track is mostly decoupled from the plastic, but i would need to keep to set track to keep by geometry neat any tidy.
Overall i think the plastic might be ok as a deck as per Duncan's work on a wooden lader but the plastic on plastic ladder is a no and i wouldn't recommend it to anyone going forward.