I am in the process of doing a front disc brake conversion on my 63 cat with a kit from auto city classics. Like scarebirds kit it has a bearing spacer. but no instructions as to where it mounts. I think it goes behind the rotor on the spindle but it will not slide all the way to the back. does anyone that has done this conversion know if it is a press on fit? It is a couple thousandths smaller than the inner rear bearing diameter. Any help or instructions is appreciated.