You might want to check the New Mexico archives in Santa Fe New Mexico.  If
my memory is correct, they have original government documents from the
Spanish period.  A copy of much, but not all, of this material, is in the
Library of Congress.  There is also a published finding aid to these
documents.  Being that much of the earliest period of Spanish documents is
likely to have been destroyed, one would want to also check the Archivo
General de Indias in Seville.  I suspect that many of the earlier documents
pertaining to New Mexico at the AGI have already been published by Frances V.
Scholes, and others, many years ago.  A specialist in New Mexican colonial
period history should be able to tell you more.
 
               Lawrence H. Feldman
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