Originally the exhaust outlets/tips passed through the rear valence panel as an aesthetic/cosmetic feature of sorts, whereas perhaps AAR believed that absent a belly pan pressure beneath the car might be modestly relieved for employing the perforated part? Of course, the fuel cell housing seems to cancel out most of any slight benefit afforded here. I'm not certain myself, although a few photographs do depict this feature and hence I felt it best to add them to my model. Given the bodywork will be painted a dark color versus the light gray chassis finish, such will be more noticeable than not.
Moving along, below I've tried to work up the distinctive impact gun alignment fixture/ring affixed to the Minilite wheels used by AAR and at the Mission Bell 250/Riverside race by Autodynamics. The actual rings are positioned on three spring loaded pegs that are in turn attached to the wheel, while I had to drill both these and the five lugs positions in turn to mimic what is present in 1:1. Some additional detail stands to be added, although the hub guides done in aluminum tubing pass clean through the alignment fixtures with cast resin oil breathers being set on end to reproduce the hub ends inside each of the four assemblies. The three spring loaded pegs here are simply plastic rod cut to size, sanded flat on the ends, pulled through further, and then sanded again to even matters out across each length employed. Thanks for skimming this post.