10/12 Bolt HELP!!

[bsnake96]

I have a Dodge truck that has had a 10 bolt front and 12 bolt rear swapped in. I'm sure if that and tht it's 3.07 gears. What I don't know, is what year or model they are from.. I've tried matching and decoding all the numbers I can find, but without luck. All the people who post the numbers are looking for the gear ratios and such. 10 bolt front end has Casting number 458856, casting date L2070, steering knuckle number 620263L. 12 bolt rear end casting number 3896839, casting date M280, assembly code RHS K224, ring gear number 3817779 14-43. No date on the ring gear. And the date on the rear end is "M".. There is no 13 month obviously. And I assume 1981 model diffs, but 81 tie rod ends and stuff don't fit. No decoders online have worked, and none of the numbers match consistent. Desperately need to know what these are out of so I can buy parts and get this back together, any help would be appreciated!