Dick H
Please disregard the comments made by Button and Tom S.
Your car is a 57 and had a clock wise spinning distributor based on the Lucas DM2P4 model, the 40480A defines the springs, weights etc inside the unit.
In the early 60's but it depends on exact model and destination of the car, therefore there are a few years that the changeover happens. The distributor was changed to Lucas 25D4 model which spins counter clockwise.
Therefore a Lucas 25D4 will not work in your car. Their cars are newer than your car.
Moss Motors advertises the 25D4 as the replacement Distributor for Triumph TRII to IVA engines. Don't understand how the DM2P4 could have a clockwise spinning mechanism.
Button
Seattle
