Best driving route from W Coast US to Guanajuato

[jesm]

We've done your trip too many times to count, having relocated to GTO from Phoenix with many trips for home construction, then moving and now family visits.
For reasons offered above staying in USA and crossing in west or south Texas has been preferred route. The key is that bypass around, way around Monterrey. Make that work and the trip while long is just miles and scenery.
The west coast route is more diverse but just navigating thru GDLA gives me fried nerves.
You will have 10-12 hours driving in Mexico depending on crossing point and almost all can be on exxellent quality and well patrolled toll autopistas. Thus Matehuala becomes an easy mid point and overnight stop. Its a trip you will love and never forget.
Once here for a while you will see that a yearly "border run" can be a single ten hour sprint without cares.
Bienvenidos!