The distributor drives the oil pump so when you remove the distributor the oil pump drive shaft turns. You can align the oil pump shaft with a screwdriver and then drop in the distributor. Or you can set the distributor in place on the correct gear and then crank the engine over and the distributor will drop in place.
Fred

1956 3100 Pickup/Red/350/3sp OD/PS/Disc Brakes
1957 Bel Air Sport Coupe/Red/355/TH350/PS/Disc Brakes
2017 Silverado LT Single Cab SB/Black/5.3/6 Speed Trans
1947 Willys CJ2A w/F-Head engine