Prep for first startup

[Floats]

Hi Guys,
I am getting ready to start my A after an engine rebuild.
My question. Once some oil is poured down the dizzy hole, how long does it take for it to make it's way to the bearings and how long will it stay there before leaking out into the sump.
I realise the quick answer is 'how long is a piece of string?'

Should I take my time, put some oil down the dizzy, replace the dizzy, put the rest of the oil down the filler tube, quick last check and then startup? Thus about 10 minutes or so after oiling the dizzy hole OR am I over thinking this?

I have been advised to turn the oil pump with an electric drill in order to get positive oil pressure befores startup. Is this really necessary?

Thanks
Chris