I am looking for a way to put on the blend door actuator

There is no bracket. There will be three small elevated plastic areas with threaded holes.

The holes so not line up but there is a 14 difference between the actuator and the blower box. The Chevrolet place says the mounting bracket is discontinued.

Then I guess the only option you have left is to find one in a U-pull-it junkyard. I am sure you will have to remove it yourself because the yard will not be bothered with something like that.