Replacing harmonic balancer and timing cover

[yad]

I need a little advice. I want to replace the harmonic balancer and timing cover on my 350. The engine is from an 87-95 vehilce, with a roller cam. Are all timing covers the same? I'll be using the stock timing gears and chain. Any help would be appreciated. I think the old balancer is out of whack, as it appears to be rubbing on the old timing chain cover. The crank does not move forward or backwards, so I think it is the balancer.