Are you sure the one on the left is a powerdoor? It's just I have observed all the fixtures in those Line Materials arms that you took pics of are one door......
The very first M-400 split doors used the same door as the powr/door companions. I'm not sure why they switched to using two separete kinds of ballastry doors though.
More likely it's a non-PE unit. The old M-400s depicted had no P-cells, so that's what we have to go by. If there were P-cells, the M-400A1 would either have the external twist lock P-cell or the internal Astrodome P-cell.
My guess this could be a split door version like Michael's light. With the screw and vents instead of the latch.
Not sure about this one.
I did notice for the lights down here, most of them have Taped up PC's to work on the relay they used.