I think the black metal piece you are referencing is the sway bar cover and it should be removed to install the skid plates. It’s only there on the LC trim.On the middle crossmember where the front of the transmission skid bolts down, there was a black metal piece on the drivers side that seemed maybe in the way. I unbolted the 2 forward bolts of this piece then just placed the transmission skid over it then rebolted the skid plate through everything. The front skid then overlaps over this area, and it worked out. (Some had mentioned installing the front skid first, then sliding the transmission skid under it..)
I wasn’t sure if I should’ve removed this metal piece, as it seems like if I removed it, there were 2 hooks in the transmission skid that could’ve threaded through some of the holes in the frame crossmember to hold it up. With the plate in place, the hooks were too low to thread anywhere. But, I left the piece as it covers some wires and such on the drivers side.