Nice setup! I love the ability to customize the software and such. I have been researching, and wanting to do this for a few months now. I found a nice "off the shelf" version, but unfortunately it only has 3 positions. I would like 4 at least, P,R,N,D. Not too concerned about L1 and L2, as I do not plan on really towing anything heavy

(I have the 4T54eHD transmission on my 3800SC swap)
I am no good at electronics,
is this the setup that you did?
Here is the link to the 3 position oneAnother fail safe I want to incorporate, is to not allow the transmission while driving, to go to either Reverse or Park.
[This message has been edited by JohnWPB (edited 12-17-2017).]