This is where it gets complicated .
You need to know what you are going to do with the car & what regs apply .
If it is going to be under FIA Historic rules , then this is the latest FIA app K .
https://www.fia.com/historic-regulations
You will then need to read up FIA app J for the period that applies .[ This can vary under event rules .
You then need a copy of the Homologation .
https://historicdb.fia.com/sites/def...05_group_2.pdf
That should be the one .
After you have read up that lot , you might ??? have a bit more idea what you need to do .