Go to your local paint supply store take your vin number and under the hood on the firewall their is a code plate take those numbers.
ppg and dp color codes is what will match the original colors as DP is what GM used on our cars. the supplier will have paint card for manufacture and model and year when I tracked my t type down I got every color code and color on the car to include trunk and interior metal spackle primer. Find the person who the hot rodders are talking to, he can set you in the right direction Just a suggestion