I respectfully disagree with the above post. I believe Ive seen the same build you are referring to. Was it the one built on a Phila Ord receiver? If so, I thought it came out more representative of a full auto Thompson then any current semi auto on the market. How can you run a Thompson when its a new receiver? Ive seen the same build using welded receivers. How can those be ruined when they are already cut up? A deactivated gun is just a fancy paper weight, now matter how original it may be.
In many countries, deactivation does not touch the receiver. Most receivers are still 100% although I know that the new spec deactivation in England isn't anymore.
I know there was some that it was discussed in another thread, but there was a website in another country that was selling modified original 1928s to semi configuration. I'll have to see if I can find the page again.