Magnum mount issue?

I had solid mounts when it had the 340 and sorry it had some very nice rattles etc I just thought the mount may be causeing havoc as the engine moved, locking up prematurely or somethign jsut screwed inside it. I replaced the tranny mount with no real change.

The torq is a Dynamic brand and it lived behind my internally balanced 340 without an issue.

As far as the engine goes I assume the flexplate was balanced with things as it came with the engine as far as the balancer goes I bought it on my own and was never asked too much about it. Unfortunatly the engine deal is a long distance thing from a very reputable person, needless to say I'll keep my engine jobs more local now.

I'm told the engine specs and numbers came out very very well still need to get my spec sheet to say any more.

I'm going to swap to the balancer that came off my stock forged crank 340 and see how it runs, as worn out and badly rebuilt by the previous owner as it was it was as smooth as a top.

I'm just drawing at straws here to find all the little easy things before I point to a base engine issue. Because then its a world of hell worse then now.