I put cab lights on my 64 C-30. The hardest part is chasing the wires! I used an old speedometer cable, as they will bend an conform, but you can still "push" on them pretty hard. It was time consuming to say the least, but was worth it! Good luck........

1964 C-30 http://s1179.photobucket.com/albums/x383/autoart3/64%20one%20ton%20dually%20flatbed/