engine build date code explanation

  1. ChxrlieRxe

    Number welded over the engine block code-- does it indicate a rebuild, junk yard pull, or warranty service??

    I have the original owner and shop manual for my 1987 laredo 4.2L, which means this engine was built 02/05/1988....the "8" indicating it was built in the year 1988, and since the jeep is an 87 I am assuming this is not the original engine; but what the heck is the additional number that is...