HELP!! Au xr8 series 1 Running rough,

[blue oval joe]

Yep, new leads and plugs fixed the misfire and it running rich (carbon particles out of exhaust!). But it didn't fix the rough condition, turns out it was the harmonic balancer, it had rotated 30 degrees. Had one go in a 95 fairlane and it nearly shook my back teeth out! This one, the vibration was around 1000 and disappeared at 1500-2000, weird.
Thanks for your assistance, I hope this info helps someone else.
All the best.

Cheers, Joe.