Connecting rods

[Cummins9912v]

Hi I just recently took the connecting rods out of a block I'm getting bored and had two rod caps left over and i forgot which one goes on which rod. I didn't know if there was a number on the rod and the cap that match? I just feel stupid for not putting the caps on when I took the pistons out haha. Please help!
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[ahale2772]

there is usually a laser etched marking on each cap/rod that matches them

 

[Tnspark82]

^correct. If you can't find any marks clean them and put them both together by hand with out bolts. There should be something so you can tell which one came from where.