You're getting some really bad advice from Moser! I would think that an outfit like that would know better, or at least be willing to correct their mistake. You're going to need to find a machine shop with a Bridgeport mill and a dividing head to lay out the hole spacing, and solid carbide drills and milling cutters to cut the holes. They will need to spot-anneal the flanges to make the initial cuts for the 5-stud spacing.

I'd make a guess that about $100.00 worth of carbide cutters and a real machinist should be able to get you back in business!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
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