Engine Mounts replacement with Headers, NOPE.

[Vette40th]

I have been fighting a slight vibration in the 93 for some time.
It could be anything, except engine. Engine is a 396LT1, Moreperformance.
AC clutch died years ago. Replaced it, so it may be the compressor due to only having 1 bracket mount to block vice all oem due to headers. Never had it before clutch replacement. Never drove it much though, to be honest in summer with AC on.
Balancer was changed too, but, LT1s arent externally balanced there.
Now with ac on, I feel it. When Off a little. That will be another story.
Yesterday, I decided to change the engine mounts ( original from July 7, 1992), 154000 miles. I heard they can go bad, and I had two in a box.
Long story short, with Headers, it will not come out. Gave up
But, there were rocks under the mount. Mount looked great. No rips, tears, etc.