Tool;

Are you sure you are dealing with a 350 or small block? Some early 366/427 tall decks had the square pump drive for the distributor. If you have changed the pump and drive, did you change to a slotted drive? If so, just take a screwdriver and turn the pump drive to line up with the distributor when you drop it in. Do you have a pic of the engine? That will clear up a lot of questions. Also the 366/427 tall decks have a longer distributor shaft to make up the difference in the deck dimensions. Good luck.

SimS