Well, I put the car on jack stands, and put a 2 x 4 of wood and lift the engine to replace the motor mount, it has one horizontal bolt and two vertical that are accessed under neath. I screw the bottom ones about half way and than I dropped the engine with the jack, I made the mistake to drop the engine too much and I think I stripped the threads (I assume because now both bolts do not tighten). Short of me re-doing the job all over what can I do? Now I cannot tighten them, but I also cannot loosen them. What can I do now? could feel the engine life on fast accelration or reverse, please help with any ideas.