Database Char set changes : Is there any way to avoid data truncation

Hi Gurus,

As in the title, our company need to change the database character set for our EBS envoironment, from ZHS16GBK to AL32UTF8. Now the issue is, from the csscan result, we can see that there any many data will need to be truncated before we can migrate the character set. Now my question is, is there a way to avoid this data truncation ?.Maybe a tools from oracle or in the market that can help us, or maybe a trick or whatever a way so we can migrate whole data without being truncated ?

Thanks in advance for all the advice from you.