Back in 1982 when cross border trucking ended, company owned Mexican trucks were still allowed into the US.
And in 1996, Clinton didn't allow the Mexican trucks in, but Canada did, so there are Mexicans trucks crossing the US to reach Canada.
Hang around I 35 from Laredo to Dallas and I20 from Dallas to Little Rock and you will see some.
Although Heritage did a good study on that a few years ago, also. If your company decides to send a truck on a intracontinental, international jaunt, then it is likely to be in good working order.