Mi twenty-six times over cousin Rosalinda made a big breakthrough for 
me today looking through films for me.  I had not been able to find a 
link between by fourth-great-grandfather Joseph Ramon ARANZAZU and the 
families in Tlaltenango with that name (where he supposedly was born).  
She made the link but it was not what I expected.  I am posting it here 
so that I can get suggestions as to how to proceed:

I looked up the marriage record of Ramon, and while the IGI notes that 
he was married before, he was not.  The person extracting the record 
misunderstood.  Ramon, it says, is an "expuesto en las puertas de Don 
Bartolome Aranzazu."  Since he was left at the doorstep, I guess his 
parents are unknown, and I think your brick wall is now truly high.  
There is a chance that you can find his baptism record, but that would 
take some work.  Sorry about this news.

Also if anyone has any ideas as to how his son ended up getting the 
name RAMOS (Benito RAMOS)... My guess is that son of Ramon (orphan) led 
to RAMOS, though his other children seem to have gotten the name 
ARANZAZU.