delete and Change dell service tag dell m170

[kentuckynet]

Hello i have read a couple of closed threads on this site about changing service tags on dell laptops.

I have a Dell M1330 and dell xps m170 both of which i have replaced the mb's with used ones and now the numbers dont match...........

I know that only dell techs have this info...blah, blah blah

I bet someone else does too........This is the person i need help from

Thanks