Its 59ft lbs for the IRS brackets that bolt into the exact same spots so I'd just set it to 60 with some blue threadlocker and go.
2000 Mustang GT Steeda #0048 34k miles. 99 Cobra 4V swapped, FTBR IRS swapped, exhaust, tuned by James Gordon.
Just because I give you advice, doesn't mean I know more than you. Its just means I've done more stupid ****.