My speedometer is reading about 15 MPH faster than what I am moving. What Gives???? Did the new internals have something to do with throwing my cable out of whack??? Do I need a new cable????

Thanks in advance

Later

 

Sounds like someone put the wrong speedo gear back in it. Usually a bad cable will read slower than actual speed.

 

I agree with ThegreatJ, also isn't your speedo electronic? VSS?
Also they are color matched so if you remove the VSS gear, see if the output gear is the same color?