Windo-weld is shit. Get real urethane. 60 shore urethane will transmit less vibration and last whereas windo-weld tends to fail because its not meant to bear loads.
The NVH comes mainly from the prothanes contacting the brackets connecting the chassis/cabin directly to the engine. If you make your mounts so there is some space in there it makes all the difference.
Or like I said you could stop being a little sissy.