Im in the process of putting disc brakes in my 53. Went for Scarebird as you will see down in Driveline. Yes I had to grind off about an eighth of an inch from the calliper
to fit my 16inch wheels. There is a lot of meat on the calliper so didn't bother me. Trying to find a booster and dual master to fit is another problem. the tech people at various vendors are not overly helpful. If you have a manual transmission that can be a problem as well as the cross member. I have an automatic tranny so that is one problem out of the way, but even the rear cross member may have to be butchered.