I have the pod screwed up tight, dummy motor and axles to keep the pod and axle holders straight. A sliver magnet under the guide to stop it sagging, while it is pinned from above by magnets.
The small triangle of weight behind the guide is there for life.
As per the picture, I gave it the same boiling water/plate treatment I would give a Ninco, Slot.it or Scaleauto - anything else with a basically flat under-pan.
By chance it sat in the cooled water a couple of days. When I removed it yesterday, the chassis tried to curl up into a foetal position and play mostly-dead.

I have since done another treatment, using 80c water, and without the central pod weight; and this morning it looks to be staying flat.
But I am wondering what others do, as boiling water doesn't seem to agree with the plastic composition of NSR chassis.