Just visited this truck today at lunch. I know it's been referenced here in the past, but I had to post this since these may have been the best pastor tacos I've had in my life. Tortillas made by hand -- tacos are $1.25 each for pastor, carnitas (both excellent) and everything else except tripe, which is $1.45 I believe.
I think other CH'ers have mentioned ther limited menu at these trucks. I'm not sure what is or is not available, but the taco selection is extensive. So if you want tacos perfectly prepared, head the the cart in the parking lot at N. Killingsworth and N Denver. You will NOT be disappointed.