In 42 years, I think we have had two Model A motors in for re build with a Mix, of steel, and brass shims. I have no doubt Ford had made some out of steel for parts replacement, as they also made some out of brass, as we have used up years ago. STEEL SHIM STOCK, has NO PLACE NEXT TO ANY ROD OR MAIN BEARING, PERIOD. Their in not one engine manufacture is the U.S. that has used steel shims in there engins when New. The only time any body used steel shims, as both brass, and steel were available, AFTER MARKET, but steel was for only one reason, CHEAP, CHEAP, CHEAP. Steel shims when you align bore, if the cutter hits the shim, in which it always does, the cutter will instantly pick up a steel chip, and always deep grove a finished bearing. Steel shims are prown to be magnetic, holding and recycling metal deposits, from what is coming off the shim from wear, or metal from else where. If a motor sets over winter, or longer, in unheated storage, on cool high moisture days, and you lift the hood, and the motor is sweating, the inside of the engine is getting the same. Steel shims will build frost rust, as will the crank, in the oil pockets, and guess where that goes, that is why you should turn an engine over once a month. Many engines came out with thick steel, or brass filler plates, BUT they are away from, and do not touch the crank, and as always have BRASS shims, from .006, to .032 thousandths laminate. The metal that is used in the filler plate is a soft metal that will not magnetize, but the steel shim material can. Its bad practice of not putting in enough shims in a bearing before you bore the bearing. I can not say for sure, what Ford had for shim pack thickness in his rods, or mains, but I do know that round, bored hole that the Factory made when new, with their shim packs, are LONG GONE. You have to have any hole round, before babbitt, no matter if it takes .016, or .032. Why, because the caps have been, filed, or machined so many times, Plus you are moving the cap in closer to the rear slinger, try to fit Terrys seal into that egg shaped hole. I have had .032 shims not enough to make the hole round, in that case, we pitched the cap. If you use .006 thousands shim, and the hole need .020, you are really making the babbitt weak in the cast cap also. Another false statement is brass shim packs keep compressing, because they are soft, THAT IS B.S. in the bigest way I can express. We torque the bearings at what ever Spec's, Bore, and in the case of main bearings, set crank, and retorque, end of story, can you tighten the clearance with over torque, yes, and you can do that with NO SHIMS INSTALLED, but what is the point. Glen, if you had to add shims to a N.O.S. Ford rod, to fit a N.O.S. crank, some body had robs shims, or they were not Ford N.O.S. Herm