It’s often claimed that the little Messer used parts, tooling or even the complete cabin from the Me-109/110/whatever numbers Nazi fighters as a means to cheaply make a car. According to the research I’ve done and most actually thoroughly researched sources I’ve been able to find, not true. Not true at all.

ME-109G-10, one of the ultimate versions of the fighter
Early-mid model Me-110 (later models primarily distinguished by engine upgrades)

The best of my research and corresponding sources conclude that the fighters and the ‘roller have absolutely no parts commonality whatsoever (the planes would’ve been made of aluminum, and it seems the little ‘roller had an all-steel body). Nor do they have any commonality in tooling. While both planes certainly had cramped cockpits it seems the ‘roller was even more cramped, and the dimensions, structure, materials and everything else don’t line up in the least bit.

Research suggests the cockpit-like cabin of the ‘roller is one part coincidence, one-part tangenital. The ‘roller descends from an invalid carrier designed for, well, invalids, so a long and small cockpit would allow such a person maximum mobility with maximum ease of ingress/egress. It seems that the most actual commonality between the car and the planes is in the skilled labor used to construct them, with construction techniques being “close enough” such that laborers and assemblers didn’t need excessive re-training to put them together. But that seems to be it.