Ok thanks.
Thats black and white wires hooked into the grid the transformer is sitting on, in the first pic I posted.
Plus this is on the cab floor...

With this wire attached...

but not connected to anything? Monitor comes on etc... but I just want to ensure that I have everything plugged in right so that something doesn't blow, that's all. Don't feel safe working on it until I know. Any ideas here?
Thanks