Think of it like this:
In San Diego a panel would be directed South at a 27 degree angle for a fixed mount. In July/August/September, the angle is better if like 14 degrees. In June-September, facing South-Southwest is optimal over the other months. In the winter months of October through February, the panels do best facing South, but you can raise the tilt to about 36 degrees.
Since you have a mobile situation, you can adjust your tilt and direction accordingly. Just find the right places on slopes to park and you are home free!