4l80e swap question
The neutral safety switch should be the same. The round case connector can be repined for the 4L80e which will give you also the second speed sensor wiring; the wiring is already there, just need rearrangement. Same at the ECU end. It's not that bad to do.
There's also the option to swap the input shaft on the transfer case originally from your avalanche. From 27spline to 32spline.





