Who Runs a Manual Automatic?

It might be a bit late lol. But I am having a manual valve body put into my Turbo 400 while in for a good rebuild.

Eventually this will go behind my 468 BB in my 73 with a 3000 Stahl TQ back to 3.73 gears.

I have a 4l80e behind my 468 twin turbo, if I flip a switch it goes to manual. I have the normal/manual switch as well as the upshift/downshift mounted on a small bracket fastened to the shifter and you run it with your thumb to shift up or down.