Instead of drilling four more holes, which may or may not line up given you're going to have to measure the offset and provide it to them, why not find a machine shop that can "Slot" the existing holes say 1/2" on either side of it? You will have a range of adjustment then and can tweak it as you desire. Would be a real pisser to drill 4 more and be a fraction off......
Can you explain this in mre detail? Thanks.
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