Hi, @mikenr
Welcome to the forum.
Please read the post at the start of any forum , entitled "How to use this Forum".
@mikenr plan.
You could do it that way, but how would you know which way to turn to get the maximum combined output.
The usual way is to read each sensor and compare them, the higher sensor will be at the closer angle to the sun.
You then turn your PV panels in the direction of the higher reading, until BOTH sensor values are equal.
Google;
arduino solar tracker
This simple flowchart may help.
Tom... 
