Think I got it solved tonight.
I tried replacing the vacuum line for the trans, but that didn't help.
So to I tried different shift points.
I had been running a Madwolf tune, with his shift points for a 3.42 car.
Tonight, I loaded my stock 2.73 file, converted the shifting for 3.42s and copied that table to the Madwolf tune.
The 1-2 shift is now set at 38 MPH, and the 2-1 downshift at 23 MPH, that's a 15 MPH difference instead of the 4 MPH shown above.
Loaded the file to the car, and went driving.
Got to a place where I was alone, turned off TCS and nailed the throttle. The tires spun all the way through first, and part way through 2nd. No downshift.
Before, the car would spin the tires, then hit 2nd and immediately stop spinning, then downshift, then upshift and bark them hitting 2nd the 2nd time.
What I think was happening is that the tires would start spinning, wheel speed would come up above 34 MPH, when it hit 2nd, the wheel speed would drop some, below 30 MPH and the car would go back to 1st, then when it hit 34 again, it would go back to 2nd.