9in vs 10 in Spindle

Will the 9 inch and 10 inch spindles bolt in place of one another. I have 9in drum brakes on the front of my 72 Demon. I am putting on a wilwood from disc brake kit and it is the 10inch spindle kit. I have a 10 inch spindle i just need to make sure that it will both in place of my 9inch spindles.