The Birth Certificate for my '57 has just arrived and it includes the following unidentified M - Codes; M 008, M 042, & M 108. I'm pretty sure these often show up on peoples Birth Certificates as unidentified but thought I'd mention them here in case any of them have now been identified.
Incidently, it also showed M 018 Larger reflector in brake light / indicator light, was this common to all beetles imported to the UK at this time.
July 1957 UK supplied RHD Oval. 1972 World Champion Beetle. 1978 UK supplied RHD 1303LS Cabriolet. 1973 UK supplied RHD 1303s.