Are you sure about that running weight?
My friend who has an all steel original 62' Max wedge with full interior, full factory glass, cast iron ram horn exhaust and pipes all the way to the bumper, three speed, weighs in at more or less about 3300 Lbs on my digital scales.
Have you weighed your car on certified scales?
That's a bit heavy for such a car.

I know that Blowers can be heavy on a car though, but not that much. Is the partial cage full DOM steel?