they are very easy to set up once you wrap your head around it,the original ints are kind of vague or at least I found it to be ,you can set them up on the bench and put them on with the pulleys installed,and your engine in the correct position ie find tdc on no 1 cyl then use stock auto advance to turn engine to full advance, if you have the pin for the mag drive set right you can drop the mag on bolt her up ,run your wires and start it up no prob.they run at full advance usually,but can be set to the number of deg retard or advance you want but it runs fine on my bike as is full advance.to change the advance you would use a deg wheel if you were looking for an exact setting.this is the first time I have ever set one up so it cant be that hard,but I have set lucas mags before.bill