Pat Johnson has done a nice plan for a Ringmaster "Lite". It shows the orginial S1 OTS design but also shows enhancements that can be made to make a light weight version. e.g. 1/16" formed LE or cutout LE, alternative wing spar design or original, carbon fibre pushrods, honey combed plywood parts etc These mods are intended to get the finished all up weight to around 23-24 oz and make it only suitable for a .25 engine or smaller. And it is still OTS and PAMPA legal.
Cheers