I could use some help fining a birth record(read post for more details)..

I'm trying to help my grandpa's half brother trace his father's side of the family. He unfortunately doesn't know the names of his paternal grandparents. His father Manuel Saldana was probably born sometime during the 1890's possibly somewhere in Jalisco(i'll get into that a bit later).
Back in early June, I dna tested him and finally got the results earlier this week. He had some second cousin matches that didn't match my grandpa at all, indicating that they are related to him through his dad Manuel's side. I emailed this person, and found that those matches(who happen to be full siblings) relate to my great uncle through their dad's side. It was also mentioned that their paternal grandfather came from jalostotitlan, and that their paternal grandma's mom was from some place called Rios Bolivos in Jalisco(which i can't find where in Jalisco that place is). I've tried looking for a Manuel Saldana in the Jalostotilan church records with no luck. It would be awesome if i could trace his dad's side as well, since I've been able to trace my great grandma Lupe's ancestry several generations further.