Wills & Testaments in Colonial Mexico

I am trying to learn how to access the last will & testament of Antonio de Aguayo. Through the LDS Library in Salt Lake City, Utah, I found that this document is in the archives of Guadalajara but access is restricted. I would like to know if anyone has researched Antonio de Aguayo, third son of Martin de Aguayo and Catalina de Ledesma of Portillo, Spain. Antonio de Aguayo came to new Spain in 1525 and served under Nuno de Guzman in the pacification of Nueva Galacia in the early 1540s. He filed a Probenza de Meritos y Servicios in 1572 listing his wife, Juana de Padilla and five un-named children. Because he didn't list the names of the children, I find it difficult to make connections to other Aguayos listed in various publications and records starting in the early decades of the 1600s. Can anyone help bridge this gap?