Car vibrates when in gear
 

Hi,

I have a 92 Integra GS with a replaced motor. When in neutral and engine
running, no vibration at all.
But when I stick the gear into D, then the car vibrates and when I stop at a
stop light.

Any ideas why the car vibrates when in gear?

Motor mounts? If motor mount was the problem, wouldn't it vibrate all the
time, even in Neutral.
Rear transmission mount? Anyone know where this is located and is it easy
to fix?

Thanx in advance for any advice.