I six speed swapped my truck a few months ago it is a 2003 cummins and I have a push button tcase that I had to be in neutral for it to engage 4x4 low but now after the swap I have no 4low does anyone no what controls the neutral safety to this my neutral safety is already crossed on my tranny

 

I had the same prob when I did a 12v getrag in a v10 auto super duty. I went to my local tranny shop and they printed me the wiring for the auto to tcase. There was one wire I had to short so the tcase " thinks" the tranny is in park, then I press the brake and in 4lo she goes