Broke down the front and rear wheels and sure enough, the welds were a little on the fat side inside the rims. Carefully used a file to shave enough of the material off without creating any sharp edges and now both wheels randomly settle with the valve stem oriented when spun while the bike is turned upside down. That's solved.
To verify, here are pics of the front wheel. The first pic was taken about 4:18 PM demonstrates where the wheel was settling every time I spun it and it came to a complete stop. Other pics taken after 9:30 PM demonstrating the various random positions the valve stem settled. spins were roughly 2 minutes apart for the pictures taken after 9:30 PM.