Well the daily driver did all the work for the Nationals and in some cases it was easier using that as I had more room to cart things about.
Today we removed the overdrive unit and had it on the bench and in this situation all worked well. So now it will go back into the truck and we will again try to work out why it does not want to work in the truck.
Today we removed the overdrive unit and had it on the bench and in this situation all worked well. So now it will go back into the truck and we will again try to work out why it does not want to work in the truck.

. Now the Auto Elec found nothing wrong so we have concluded it could have been dust or moisture. Either way I have a spare now if it does happen again. I have put the old one away and left the new one fitted. I hope never have this problem again.