Ford 2003 Mustang Workshop Manual page 1793

3. Using the data recorded earlier and the Bearing Select Fit Chart, Standard Bearings Chart
determine the required bearing grade for each main bearing.
Read the first letter of the engine block main bearing code and the first letter of the
crankshaft main bearing code.
Read down the column below the engine block main bearing code letter, and across the
row next to the crankshaft main bearing code letter, until the two intersect. This is the
required bearing grade for the number one crankshaft main bearing.
As an example, if the engine block code letter is "F" and the crankshaft code letter is "D,"
the correct bearing grade for this main bearing is "2."
Repeat this process for the remaining four main bearings.
4. If oversize bearings are being used, use the procedure in the previous step and the Bearing
Select Fit Chart, Oversize Bearing Chart to determine the required grade for each main bearing.