There isn’t any film of Mitt himself in that regard, but when American Motors went under and was being dismantled, laboratory film did surface for a while (it was claimed), of what it’s few observers described as some form of a “humanoid assembly kit” in an early development stage, but the story faded in time since it’s purpose, or success, or failure files never surfaced, it was assumed that the research had been a costly failure and abandoned.
There is a lot of technology out there that hasn’t reached consumers, that we hear nothing about.