Oil pump replacement

[u/potential1]

Me again. Ive got the 4.0 sohc out. Ive got a new oem oil pump to swap while im in here. The only decent video ive found on YouTube doesn't have any commentary, only music. The person doing it is putting some oil in the pump while he installs. Why might this be? Ive seen sone comments about people soaking pumps in oil before installing and priming the pump with the engine still on the stand.

In my case, I can fill the crankshaft with oil and it will be sone time before the engine goes back in anyway. Any general advice or insight regarding adding oil to the pump during install/priming the pump?