Just in case of any doubt, this includes both checking visually that everything is in place with no damage/wear, bent wishbones/rose joints etc. But also critically what you'll often hear called a spanner check. Physically checking with a spanner and wrench, that all nuts and bolts are still appropriately tight.
Even perfectly standard Westfields just don't have all the bushes and NVH fixtures and fittings of a modern car, plus, relative to their weight, tyres and suspension are often stiffer, so even on the road, let alone the track, all the parts and fastenings tend to be subject to much more vibration than a modern car. Throw in heat either from pounding round a track all day heating tyres, brakes and engine/transmission up, which then heats up everything around it, or even just hot summer weather. And nuts and bolts can and will work loose occasionally.
Hence the spanner checks!
(This is also something worth doing periodically even just on road going Westfields. Depending how much it's used, once or twice a year, check nothings about to fall off!!)