Hi Miguel greetings:
I use a lot this page when I have doubts regarding the related tables for a specific transaction. Hopefully this will help you too:
http://www.tcodesearch.com/sap-tables/search?q=f-32+-+clear+customer
The other way i know is by using the st05 transaction, generate a test payment and check the trace results. It can be tough but you can find the information you're looking for 
.
Hope this became useful.
Warm regards
Lorenzo Martín Olmos
Message was edited by: Lorenzo Martin Olmos Vega