[James Lamb]

The early ones, as far as I understand, have the same internals, same gear ratios, same case, so it all bolts up without modification. But the 4l60e is electronically shifted. So you get rid of the ridiculously finicky tv cable and the pressure issues and burnt clutches that frowning at it can cause. I'll be able to program shift points and firmness and based on other vehicles I have owned that had 4l60e's stop worrying about the transmission crapping out on a near constant basis.