The 67-72 drum carries 2 bearings in it (i.e. only one bearing in one side of the OEM hub). that area will not fit over the 36-66 star hub, at least not unless you do some machining. I'm not certain whether the hub and drum dimensions are otherwise the same, meaning that if you did machine the middle out of a 67-72 drum, whether it would line up properly on a 63-66 wheel/brake setup. i'd be interested to find out though.