Year mod. of engine?

[lincoln]

I have a 92 3/4 ton 4x4 and on the cab it says 12/91, I have a 93 1ton drw 4x4 that says 3/93 but so far everything Ive seen on the engine is the same. It realy doesnt matter I was just wondering if they both had origianl engines like the previous owners say. This may be a stupid question but Im new and want to learn as much as possible. Ive always owned diesals other than a few when I was in school, but I finally got the 2 trucks Ive always dreamed of owning and want to no as much as possible. Thanks

P.S. Ill probably asking more dumb questions once I have enough money for mods. Any advice is welcome and apreciated. The 93 is for work Im a welder and the 92 is for play.

[Philip]

About the only difference between the enignes is the 92 has a 21cm exhaust housing. The 93 has a 18.5.

With a build date of 3/93 that is the latest date I have seen listed. Most of us have 12/92 dates.