[BillM]

In case you missed it there was a post recently about the specs on the relief valve spring; here is a quote: Here is that information from a '48 manual:
Oil Pressure Regulator Relief Valve-Check relief valve spring tension and replace spring if tension is less than 78 ozs. or more than 87 ozs. when
compressed to length of 1.380".
That might have been your post; I didn't copy the author; in any case I am interested in your findings.