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I wasn't aware of any bores being out of position. Are you saying the spacing of them is "off" what's normally referred to as the "center to center " measurement. The distance from the IMS bore to the Crank bore is easily measured and calculated. Take a vernier and measure the widest spread from bore to bore using the outside of the caliper jaws ( which has a radius) if you had bore of 85mm ( which is what the Rear main seal is) and a center to center dimension of 130mm and the IMS bore is 60mm.Add 1/2 of each bore plus the center to center size and total them up. 202.5 mm would be the size you're looking for. Of course when we use an ID mic. we get an exact size so the 85mm may really be 85.02mm, all this is calculated into the equation to arrive at the correct dimension. Correcting an issue of center to center from the camshafts can be addressed too. Just a little bit more math is involved. Trigonometry is used to calculate the angles and centers. If an engine was way out of spec on one bank there is the possibility of moving the IMS bore over a few thou to bring it back in to specs. If that was done then the IMS shafts plain brg. at the oil pump end would change slightly and change the load pattern along the bearings centerline. If you moved the IMS brg. bore sideways 10 thou. and the shaft was 10" long you have just skewed the shaft sideways 1 thou per inch. if the plain bearings journal is 1" long ( which is about right) you have side loaded the bearing and this will alter how much oil the IMS journal will ride on due to changing the oil wedge the shaft sits on while running. Even though that end has the oil pump gears on it and it basically runs in an oil bath it still has to have the correct wear pattern for the journal to ride on. All of this depends the amount of misalignment found. What happens in real life is the bearing may bed in with no problem and run for years or get hot and wipe the bearing and fail. If an owner suspected a problem then measurements can be taken to see how much a bore would need to be moved and then reposition the tooling to rebore the IMS on center. Lots to consider when issues like this crop up.
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