Edelbrock 1407 with TH400

[Longhorn Man]

I am by no means a tranny expert.
With that being said;
I have NEVER heard anyone ever even imply that the TH400 was the same as any of the other trannys that you listed.
A 2 speed jet away has very little in common with a TH400, except for theory of oporation, and if we are going into theory of oporation, we may as well call it a C6 or put a dodge logo on it. A 4l60, or 4l80... and esp the E versions of these 2 trannys, are very complicated pieces, and are distant cousins, if anything,to the TH400.
The kick down button shown on the lead photos is correct. All the 67 - 70 GM trucks that came with a TH400, also came with that button. Starting in 71, when GM went to a cable type throttle contolr, they installed a slider type switch under the dash on the accelerator pedal.