Upton
Quad:   King Mountain & Castle Mtn., both have spot el. 3141'    Castle Gap

King Mountain	
LiDAR	958.42m/3144ft -102.26623 31.28640  USGS one meter x76y347 TX West Central B4 2018 
  
Castle Mountain
LiDAR	956.42m/3137ft -102.29114 31.30299  "" 

Data from https://apps.nationalmap.gov/3depdem
Note that both these tops are very flat, and the highest LiDAR
contours cover a lot of area. The LiDAR Lat/Long locations are approximate.