There are a few options and I've used most with good results.
-I've used solid mounts both sides on a street/strip car.
Shook the car pretty good but still was not unbearable.
-Solid mount on the drivers side and rubber on the passenger
Less vibration and good support especially for high torque big blocks and 4 speeds.
-Set of cheap rubber mounts with good torque strap
-For my current setup I bought a set of Mity mounts from Dynatech
http://www.mitymounts.com/chrysler.htm might be the same thing Mancini is selling definitely the same thing 440source sells.
These mounts have internal locks.
First set I got made the engine sit tilted in the car, Dynatech immediately set a new set which worked after some modifying/tweaking.
Nice mounts but they still let the engine move too much in my 440 Sixpack 4 speed Challenger and actually caused the clutch linkage to flex and bind during hard acceleration.
I ended up adding a torque strap to calm things down.
