[Mark in MT]

The problem of just replacing a single cap or a set without machining in place is that the tolerance in the centering of the bearings. You don't know exactly where the last guy set the center line of the bearing in relation to the centerline of the block. Ford used the main bearing bolt holes as datum points for locating the bearings, but fast forward 85+ years and how many rebuilds by unknown builders leaves the interchangeability of caps in doubt. I advise either to get an undersized cap and hand fit it by scraping ( a long slow process), pour and bore all 3 bearings to insure that they are in line with each other. Also, a smooth, round journal is a MUST for any kind of bearing life.