Bypassing TCM for TH400 with E38 PCM

[bfurches]

I have read a bunch of outdated info and I am trying to figure something out before I finish my harness....

I have a complete harness, pedal, E38 PCM and TCM from a 2008 Savana Van with a 6.0L LY6 and 4L80e.
I want to eliminate the TCM and run a TH400 instead of the 4l80e.

If I were to go this route, and I eliminate the TCM from the harness simply jumping the serial comunication wires....would I be able to simply select "Manual Transmission" from the "Auto Shift Properties" tab? Will the car still start and run, or does it need to see safety switch inputs from the TCM?

Thanks

[DSteck]

Jump the harness, don't change the trans settings, and disable any starter check.