[Graham]

If you include a 'scratch built' event, you'd need to define 'scratch built'.

To some, 'scratch built' means built from scratch i.e. home made chassis or car bodyshell.  In days gone by that meant brass chassis and wood carved or fibreglass molded bodyshells.

To some, painting a white kit isn't 'scratch built'.

To me personally, 'scratch built' means you've made some part of the car yourself or clearly modified a standard part to suit a different car.

Yes I agree in principal, but I think you have to be realistic in terms of a "modern" interpretation as apposed to historic one. So I would not compel all the entrants to make a brass & wire chassis or make a body out of Balsa wood.....although that might be interesting challenge. And 3d printing of body and chassis are a common feature of modern slot racing, so I don't think you could exclude them although you might restrict it to the use of certain 3d materials or in the case of the motor mounts for the reason given above.

But I don't see much difference between buying a GTM kit and calling it a Scratch build compared to a Slot it white kit and calling it scratch build, effectively the modelling activities are are the same just different materials.