Just came across your thread on racing RX3s.
There were plenty of these gong round in the mid 70s in production saloons, John Bridley, Tony Lanfranchi, Gerry Marshall, Wendy Markey etc. My Dad, Terry Mayne used to race an RX3 in this class too.
My cousin Alastair Smith also raced an RX3 in the Duckhams Road Saloons around 1984. Dad tuned the engine, got lap records at Snet and Donington. Put the cat among the pigeons a bit but rotaries always did that a bit
Terri Mayne