Mostly scratch built, with a couple of details from my parts box. The WIP thread is available here, any comments/criticisms are welcome!
I used two sets of 1/32 scale P-38 main landing gear tires to replicate the balloon tire look used in the comics, which are mounted on the inner wheels from a 1/25 Batmissile and fit with almost no modification needed.
Paint is Tamiya TS-78 Field Gray, which was a nice middle ground among all the different shades used over the years.
The seats were scratch built from floral wire and 0.080" styrene, and the shift lever is a straight pin with some insulation and craft beads around the base as a boot.
The steering wheel is the last piece that came from my parts box...I was going to make one, but found this and it was too perfect to not use. Gauges are Slixx decals, and the pedals are sandpaper cut to shape and painted.
The exhausts system is aluminum tubing, with different diameters added to make the muffler.