So which bits can be retro-fitted to ensure values of earlier cars don't plummet?

And can the chassis be strengthened on earlier cars, or can the chassis be removed and replaced (horrendous if even feasible I would have thought). I have heard that chassis fractures aren't uncommon, and would argue this is an unacceptable issue to live with...

Haven't had problems with cooling given my usage. And my bevel box is fine - compensator is just about ok at the moment but hopefully that will conk out before end of warranty - I'm sure I heard some strange noises from it last time I was out!!