LS motor oil pressure at start up on a rebuild

The boy had a motor create pretty glittery kitty litter in the bottom of the oil pan, no oil pressure. 

He's done a few of these, I think only a couple have spun bearings and such. 

Is there a fool proof way to build oil pressure in these ala the old Datsun and Bimmer motors, where I pull plugs and spin the motor until I get pressure?

I'd heard that doesn't work on the LS (where I heard that I don't recall, could be fake news).

Any fool proof tips to get oil pressure before firing?

I've packed the oil pickup tube with some Vaseline to encourage the pump to pump. I may have even done it within the pump too.... or I mean you can use a pressurized garden sprayer method to do the same.

In reply to ГУЛАГ мальчик УР следующий :

I did it this way on mine:

That's also the port where my accusump lives. In the manual for the crate LS3 they tell you to pre oil via the port until you see oil pressure and then crank.

Cool, thank you all.