BAD lean spot.... any suggestions??

I had a similar problem with a Volvo 240. The cat was cylindrical with cones to taper to the exhaust. The honeycomb became a ball, that blocked the exhaust when oriented against the flow. I needed to take apart the complete exhaust to get all the chunks out. The car had fuel injection so it compensated well for mixture, it just had a great variance in power. I also looked in the exhaust manifold, it was as if sandblasted clean inside. It seemed the car never returned to full power. There may have been some issues due to abrasive wear.

This all happened in a few days that it took to figure out what was going on. A small chunk of honeycomb in the tailpipe was the true giveaway.