89 k3500 454 timing issues

[Ray62406]

Ok guys, I took a truck from a person in payment for a debt he owed me. Its a 89 K3500 4X4 dually pickup. I had to have it towed home due to barely running. It did not have enough power to pull itself on the rollback.
I pulled it apart and found the rockers had backed themselves off on 5 cylinders. One pushrod is missing and presumed inside the lifter valley.
I reinstalled the rockers, adjusted the valves and it runs halfway decent. The distributor was loose and I could not find the timing mark on the dampner with a timing light.
What is the timing specs and is there a wire I need to ground or disconnect to set initial timing? I can and will buy a service manual for it but would like any information I can get before I do. Any information is appreciated. TIA.
BTW, the engine is orange, I don't believe Chevy painted their motors orange that late in life. Am I correct?