This is a write up on how and what you need to get cheap poly mount inserts.
NEEDS:
1.Liquid Nails Polyurethane Construction Adhesive.
2.Duct tape
3.about 2-3 days to let harden (out of the car)
How To:
1. Put a couple of strips of duct tape on one side of the motor mounts ( to stop liquid nails from running out the other side).
2.Fill in all holes and cracks of mounts right up to the other side of the motor mount opposite of the duct tape.
Do that to all of your motor mounts (may require you to take the motor mounts out)
Worked great for me I love them. Stiffened it right up.