The last 300 with Hemi engine may be the most beautiful of all (anyway, I think it is), even if its appearance is much like that of the 300C. To spot the difference, look at the tail lights, which in ’57 filled the back surface of the tailfin, but are now smaller, although placement is the same. Look close and you will see that the "Swiss cheese" air filters are now horizontal, the seat leather is scored front to back instead of sideways as in ’57, the door panels now have five chrome stripes in their lower part. The dashboard gauges are outlined in chrome. The windshield "visor" is gone, with the smooth "dome" join of the convertible in its place. The hubcaps have their central disc painted red. The simplest check is on the side medallion, where an unquivocal 300D is displayed. The mechanical side of the car has become tamer, with cams of less pointed contour for smoother getaway and idle. Also bringing more comfort (at the expense of performance) is a choice of only five  rear-axle ratios; and cruise control (Auto-Pilot) makes its first appearance. A separate paragraph is devoted to Bendix fuel injection (see under "To Know More" below).
 
This attempt by Chrysler to make a fast sport car at the same time comfortable and luxurious was not crowned with success: Sales were a third those of ’57. Note, however, that 1958 was a bad year for all the full-size brands.