Greg I believe the governor mod will do what your after. The TF-2 kit does come with some springs but not the 1-2 or 2-3 shift valve springs which are the only springs other than the gov spring that'll affect shift speeds to any extent
Thanks for the vote of confidence on the governor thoughts Tracy.
I was going to PM you and see what you thought about the governor handling the details I was hoping for, but it was pretty long winded or there wouldn't have been any point in asking.