4R70W tranny question....?

Well here is the deal.....got the new tranny in but the speed sensor is reading about 60-80 mph at idle which doesn't allow the tranny to shift into first gear electronically.........it starts off in OD.....manually the car feels really strong and shifts well so internally the tranny is ok.......I replaced the stock speed sensor, shift positioning sensor, and reused the stock wireing harness.........rechecked all connections and replaced both sensors from the transmissions......the tranny was upgradded with a level III transgo shift kit and has 410 gears...with a 3200 PI stall...the only thing I can think of is the old tranny was really messed up and had it tuned to max all shift points and manipulated a few.....well more than a few transmission parameters........the only other things I can think of is if their is a difference in the rear drum of the tranny....... i.e. more teeth or less teeth for the electronic sensor to pick up........or the car lost its tune from being off for 2 days or arched out.....all websites I have found say that the 99-04 4R70W are Identical with the same wireing harness......Considering all the electronics are on the new tranny to include the harness it should be the same....? My car is an 02 Mustang GT and the tranny I put in was from and 04 Mustang GT.....
Any suggestions............??

"ED"
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"You gonna let an Automatic beat ya?"
2002 Zinc Yellow GT "Currently under construction"
12 sec NA auto 2V Daily driver!