Silver 62 should be a T3, and the S400 is a t4. I don't know if this is right but isn't the first number in the series what flange it is? I know the Silver series turbos are S300's
You can get s300's in either t3 or t4 and the s400's can be either t4 or t6. Might be other options too, but I know you can those that I posted for sure