M-400s, not M-400R3s. Interesting poles. Looks like fluorescent fixtures were likely the originals because of the angle and the long slipfitter section (see how the arm gets thinner right after the curves). Also, could it hurt to get a few guys and some paint and give these poor poles some protection against rusting out? Rarely do I see steel poles repainted nowadays.

Thanks for the correction*. Could be so, Id have to find a really old picture to be sure. I think even powerlites were possible too. Theres even an old pole like this in Brampton with the same arms but really short that have MV B2255s on them behind the plaza where the pyle fixtures are. Heres a streetview hard to see though even in streetview.

Yeah theres even highmasts here that are that same color brown now. Only poles get painted in "Downtown" type settings on the roadways. Usually Grey, Green or, Black.

Yeah a fluorescent setup like this is fairly possible. Repainting poles seem like a lost art here. Although I sometimes see some parking lots repaint the bottom half of their poles. I guess to prevent rust from forming. Before the mid 90s Toronto used to repaint the old (1930s?) cast iron poles holding up the gumballs and streetcar wires silver but they stopped.

Yeah I see even in my city they paint the path shoeboxs concrete bottoms with a light blue. Yeah that seems most likely the first fixtures on there.