The suspension itself...the leaf and coil springs, and the shocks...are the primary absorbers for the vibration that transfers from the road.

On the front end, the bushings mount the stub frame to the body shell. Unlike a true unibody, all the front end sheet metal is hung off the front of the firewall and supported by the stub frame. The stub frame has four bolts connecting it to the body shell, and two bolts to support the front end sheet metal. The front mounts help cushion the radiatior by suspending the core support on rubber cushions, but the rear four don't contribute all that much to ride comfort.

The engine and transmission are mounted with rubber or poly insulators as well in production cars. This serves the purpose of absorbing minor vibration. A well balanced drivetrain should not produce excessive vibration. Body mounts don't absorb much of this type of vibration.

Look at any of the new, high performance cars. The Challenger, the Mustang, the Camaro. All of these are unibody cars, and all have the suspension directly bolted to body components, and one of the first steps in further enhancing these vehicles is to further stiffen the chassis by adding subframe connectors. With the suspension directly connected to the body, where does the vibration go? It is simply dissipated across the chassis.