If you are by yourself, take a grass straw(oats work well) or broom straw, stick in spark plug hole so it rests on top of piston, then you can turn #1 'til the straw stops moving at top with both valves closed, find #1 plug lead and put the rotor pointing at it, insert in engine, as you insert the distr., the gears will rotate, make sure when fully inserted, rotor points to #1. The oil pump is driven by tip on shaft, looks like slot screwdriver, so, if distr. won't go down all the way, turn the engine while gently pushing down 'til the distr. drops in, it will be flush with the engine casting then. That slot that drives the oil pump is also useful for pre-oiling an engine with an electric drill and a home made shaft.

Ed

'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires.
'47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle.
'54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed.
'55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.