Maybe im not looking in the right place or im just not very good at looking

Didnt there use to be a list of event regulations online and viewable by all detailing the minimum requirement for all different Grades of event?

For example itd explain what a Grade 2F arena was, minimum seperation between arena wall and spectators for this Grade, then the same for Grade 3 arenas ect.

Does anyone know where this document is? - i realise it may be outdated and doesnt detail Beetles all that well for example, but its a good starting point when going through good goals to try and achieve in running an event