Geof
You can pre prime by removing the dizzy and with a long hex drive and either a drill or speed brace, wind the pump 'till you pump
oil through the engine. Cant remember which direction to rotate, but obviously the same direction as your dizzy spins, or
disconnect your coil and crank the engine untill you have
oil pressure, then crank another 5 to 10 seconds should be enough to refill galleries and get
oil to your mains.
Reconnect coil and start. Cam break in is another procedure, not sure if it is still done these days.