My question involves traffic court in the State of: California

A ticket was received for going 65 in a 70 but vehicle limit is 55 because it is a commercial vehicle. We don't want the point on the license, so have requested a written declaration. The officer did not state on the ticket (that I can find) whether it he paced or just observed the speed.

What are my options for fighting it? How does speedometer accuracy defense work? Do we have to go somewhere specific to check the accuracy? How can we fight it without knowing what method the officer used to get the speed? He was behind, so I assume pacing but should it state that on the ticket somewhere?

Thanks!