1999 Chevy Tahoe Tahoe shakey gas gauge indicator

My 99 Tahoe has a gas gauge indicator needle
that vibrates or shakes after the key is turned on.
Still reads tank level acturately, but vibrates. All other gauges OK.
By chance my fuel pump just failed(after this problem started), replaced in-tank pump assembly and check grounds at tank end. All OK. Shakey gauge before and after pump replacement. Where do I look next?

Thanks,

Jeff