Hi ! I think you should got with your 68 Percentile in CET, because here you will atleast have some college but if you want to take admission in any college through your JEE main rank, you will not get any college nit even a worst private college. At that time you have to take the help of management quota. Your percentile in JEE will fetch you a rank of 7 lacs- 10 lacs. So hope you understand and best of luck to you.