Valve timing

I am working on a John Deere Buck and I am having a hard time finding any useful info on setting the valve timing. As near as I can tell the engine is the same as the Quest. I have a manual but it does not indicate how to set the valve timing correctly it only says to put the cam at TDC. The timing gear has several sets of marks so I am not sure which to use. Any help would be greatly appreciated!

Valve timing

I am working on a John Deere Buck and I am having a hard time finding any useful info on setting the valve timing. As near as I can tell the engine is the same as the Quest. I have a manual but it does not indicate how to set the valve timing correctly it only says to put the cam at TDC. The timing gear has several sets of marks so I am not sure which to use. Any help would be greatly appreciated!