Originally Posted by HillRider

Chain rib in the small chainring and smallest one or two cogs is common, particularly with a significant difference in chainring sizes; 53/39 chainrings often have this problem while 52/42 chainring sets usually do not.

You cannot substitute an Italian bottom bracket for your English one. First, as Al1943 noted, the width difference is in the bottom bracket shell, not in the spindle and second, the threading diameter and drive-side cup thread direction are both different.