You can do 1 of 3 things for insurance on a classic car.
1. Find someone that specializes in classic car insurance (Hagerty, etc, etc.)
2.Get your car appraised and have that as reference for the insurance company for when they try to give you $1000 for your cars that's worth $10k.
3. Set an agreed up value for your vehicle through your insurance company. I know this is how we have the 68 set up through Allstate