You are basically on track. The delay and modulation was derived from the AMS 1580. On its fader return , some hi frequencies were rolled off, then it was fed into a 224 Hall setting, probably 5 seconds but with a rolloff in the top and bottom. This return may have been equalised also. We may have added a second delay but then the delays have to be timed to the track as the net effect is blurring the chord progression.
Our last tweak would be to play with the sends on all of the returns to the point that its almost recirculating out of control, which in turn is creating a layer upon layer effect.
The backwards stuff was achieved by turning the tape over and using a long plate setting. Pretty straight forward.
In working with Brian and Dan, we did have one section of the console dedicated to "treatments". All of of our processing was pluggin in and ready to be manipulated at a moments notice to achieve a cool sound.