According to Motors Truck Manual, the '55 235 settings are made with the engine at operating temp. Of course on a new engine you want them somewhat close before you start it. The settings are: intake, .006 hot, exhaust .016 hot.
I would set them a dab wider cold then recheck after warm up.
With engine in position to fire no. 1 cylinder the following valves can be set:
Exh. 1,3,5. ----------- Int. 1,2,4.
Then turn engine one complete revolution, which will bring no. 6 cylinder to firing position.
Set: exh. 2,4,6. ----------- int. 3,5,6.
