Does anyone know what shafts I need to get a 4t60 into a sunfire?
I thought about using the sub frame, shafts, and control arms from the olds, but the track width would be too wide.

I thought dimensionally that the 4T40E and 4T60E series were the same "size" but the 60 series being more beefed up?

The inboard ends are different. I tried putting the inboard ends from the 4t60 onto the 4t40 shafts, no dice.
I will end up using the 4t40 after all.

WOOOOOOOT!!! IT FITS!!!!

After sitting all winter in a snowbank, I pulled the 4t60 out of the olds just to make sure it was the wrong spline count on the shaft. The reason I thought the shafts were different is because 3 transmission shops said they wouldn't fit and so did the parts info at the auto stores. I thought I was screwed. NOT! I stuck the stub shaft from the 4t40 in there and it fits on both ends. I am sorry if anyone read this and did not use their 4t60, but I did not have the time to check last year to see if it really would fit. not only will the shafts fit in the transmission, but I can use the entire sub frame and weld/bolt it right to the bottom of the sunfire, saving LOADS of time, money, and parts.

This is going to be awesome! Maybe you can't tell, but I am stoked. This is going to be a LOT easier than I thought. If I would have known this in the first place, I would have pulled the entire unit out of the olds and stuck it in the sunfire and would have been driving it all winter. At least now the motor and transmission can get a good cleaning, paint, and new seals/gaskets before going in. I will update as the progress continues.

the question is will the computer run the 4t60?

The computer will love it because the 4t60 is still on the 3800....

I have the part numbers for the seals if anyone is interested.
National part numbers: 710158
324204