To the OP; If it added $2 in cost (A very conservative estimate), and you built 100,000 cars (also conservative), your cost to the bottom line is $0.2 million dollars. Look at the real numbers, and you'll get the picture, quickly.
Factor in that you have to build equipment to make each part, add people to add each part, etc. Would you want to buy that stuff for a part that is not, even by today's standard, necessary?
Also remember, at the time, these were passenger cars, NOT race cars, not street machines, not drag cars, not anything but grocery grabbers and occasionally, musclecars. Street cars didn't go around corners quickly back then. Frame connectors don't do anything when you're sliding around on greasy rubber donuts.
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