I'm currently researching the Battle of Guadalajara as a starting point for my 10mm SCW, with the International Brigade facing off against a combined force of Italian CTV, Moors, Legion and Carlist Requettes, so potential for a terrific variety of uniform and hardware on the table. Five films found on YouTube in Spanish and Italian but well worth a view for the original footage.
Battle of Guadalajara Part 1 - Spanish Documentary
https://www.youtube.com/watch?v=8esAzZP1hdw (https://www.youtube.com/watch?v=8esAzZP1hdw)
Battle of Guadalajara Part 2 - Spanish Documentary
https://www.youtube.com/watch?v=FMNYFY5rS34 (https://www.youtube.com/watch?v=FMNYFY5rS34)
Battle of Guadalajara Part 3 - Spanish Documentary
https://www.youtube.com/watch?v=gqsrP6YNAoA (https://www.youtube.com/watch?v=gqsrP6YNAoA)
Battle of Guadalajara - Italian newsreel footage.
https://www.youtube.com/watch?v=dRf2hotk_cg (https://www.youtube.com/watch?v=dRf2hotk_cg)
Famous Battles of the Spanish Civil War - Episode 6 "Battle of Guadalajara"
https://www.youtube.com/watch?v=uPxrRhfckck (https://www.youtube.com/watch?v=uPxrRhfckck)
Hope they are of interest.
Cheers J