340 Oil Priming Question First Start

I'll probably get on this one. Once you know that you have oil pressure ( which you have already established ). I would install the distributor and remove the spark plugs and spin the engine over with the starter till you see the valve train oiling. Since you have already primed the oil pump and have oil pressure this is the best way to oil the top end. I've done this several times over the year

Best way I can think of to kill a cam. Or the bearings or bushings in roller lifters.

It’s pretty simple to turn the engine by hand to get oil up top.

Laying on the starter to do it is asking for cam failure.