I just purchased a '96 3500 with dual rear wheels. I went to air up the rear tires but wasn't able to see the valve stem let alone air it up. I could feel it in there, but the outer tire stem was facing inward. Is this normal? Has anyone modified the air valves to allow ease of inflation from the outside? It has a decorative hub cap in place which I can remove, but the stem still points inward, so looking to make this an easier experience. Thanks