Try searching around for Uv mapping tutorials, i havnt used sketchup so iam not sure about its performance.
At a glance these models look the same,
Colt 45 peacemaker
but thier are some minor differences in details expected with using different reference images. These are minor, however considering its a cutout, its fair to say its been made by kuromi.
In 3d view, look at the hammer, notice its smooth while thiers a notch in hers. A few other things stike differently so yes thier different models. Though take this on face value, i havnt the time to install more clutter on my pc to check the meshs, its bad enough as it is for a Ocd-like person to have more than five desktop items.
Though i did Dl, to test if max9 can import, so dont call me lazy, the file sizes are hugely different, a 4mb gap between them, most likely wasted polies expected at any level modeler.
Anyway great job on this. andtry as i said looking for Uvmapping tuorials. It will help alot later on.
____
-Laz