Do shops or manufacturers usually label the computer after they reprogram it? i had mine dont supposibly, and i would like to know if there is a way that i can tell it has been reprogramed?

Most the time they place a sticker on the back side you have to remove the brain and look on the back side

Did you pay to have it done???? It will usually be about $400 or so. Whoever did the swap should be able to tell you who recalibrated it. You should then be able to call that person to discuss what was done to the ecm.

Hook it to a scanner and see what the checksum is. If it matches the little sticker on it from the factory, you know the answer. I'm not saying they couldn't change other parameters to end up with the same check sum, but it would be a lot of work for no reason.