Not a bad idea to push in the clutch also. The transmission oil is cold and thick making it harder to spin over even in neutral. I have heard of some vehicles that say to start in neutral with the clutch engaged but I think it best to always push in the clutch
It's Rare to find a M54 5 Ton Truck with the 9.9L R602 from Continental. The R602 was apart of the Series of R330-R883 Engines that were used in some Federal Trucks,and alot of American La France Firetrucks also.After having the R602,they went to using the EDNT-673 from Mack as the M54A1,and then the M54A2 had gone with the Multi-Fuel which was used in the M35A2.