My 2015 Chevy came with factory supplied extenders on the inside dual wheels. They are essentially plastic valve caps with a check valve on the end of them that replace a standard valve stem cap. You just press the tire gage or the air chuck against them check or add air. They have worked without any issues for over 40,000 miles. I have heard that a lot of people who purchased less quality ones have have nothing but problems.
I can't figure out how to post a picture so my suggestion is to visit a Chevy or GMC dealer and take a look at a dually truck. Maybe even buy two of them from their service department.
LeRoy