Thanks for indicating the torque used...
Willys Motors Service Bulletin #320, issued 7/25/56 covered all prior specs for the L6-226 engine in service manuals or Service Standards booklets. They list a range of 35-45 ft/lbs for the bolts. My own follow-up is to also replace the head bolts (if you were using the originals) as they can fail due to normal metal oxidation/deterioration over time, especially if tightened in the 40-45 range.
Jack Mueller