Taking it out is real easy, unless it is stuck, in which case people have used WD 40 or the like on the distributor base, soaking it for several days.
When you put it back in, make sure the number 1 cylinder is TDC on the compression stroke. Insert dizzy with cap off, so that rotor ends up pointing at the number one wire on the cap. Make sure upon insertion of dizzy that it sets down fully, engaging oil pump drive shaft.
Klatt, just curious. Did you get the distributor from NAPA without turning in a core?
to remove, disconnect wire from the coil, remove vacuum advance line, remove cap, remove hold down bolt and pull straight up, watch the rotor turn as you remove it and replace the new one in the same location..if it doesn't seat completely against the block don't force it, just turn the engine over a little bit till it drops in..connect coil wire,snug the clamp down bolt and retime it...then reconnect vacuum line