I've since determined there is something about the sheet itself that's the problem. Actually, upon further investigation, there are several sheets (maybe 8 out of 20) in the same workbook that result in the error. If I successively delete each sheet that causes the overflow error, I get no errors with the remaining sheets. Before I post or email anything I'll investigate further.

I was hoping the description would trigger something with someone, but I guess not (so far anyway).