You got the new distributor from a butcher! They cut the crankcase up to remove it. :facepalm: Undo the 4 bolts on the new one that holds the body on the part with the throttle arm.
Take the cap off and clean the points, rotor and inside contacts on the cap. Don't break anything! Replacement parts are very expensive and almost impossible to find. Clean things up and put the cap back on. Keep the cap and wires on. It is very difficult to put the cap on with the distributor installed.
On top of the distributor is a splined shaft with one missing spline. It matches with the female end of the belt driven shaft. The match line on the female part is in line with the line on the timing belt pulley.
Turn the flywheel clockwise until the line on the timing belt pulley faces you, rotate distributor shaft until missing spline is roughly lined up with the timing belt pulley line and stick it in. You may have to turn the flywheel a little for fine alignment. Once it slides in, install the 4 bolts.
