Hi - I've got a 95 Chevy with a bad 3.1 - I can get a 2002 "J"
motor with 10 k cheap- Anyone know what I have to change for the swap ? Thanks

if your 95 had the roller tappets, it's a fairly simple swap, just switch that from the old motor that doesn't match the new. If you have the old style ball and pivot rockers, it's not worth the hassle, find an engine closer to your model, out of a 93-95

No it didn't have roller tappets - but the 2002 one sure does.
I just swapped intakes and all sensors and the f/injectors- Gonna drop it in tomorrow.

Don't know why the lifters would matter in swap ?

I would have droped in a 94-95 motor if they only had 6,000 miles on them too- HAH !