Consumer Group Challenges 20th Century Settlement: Just as 1989 premium rebates are reaching customers of 20th Century Insurance Co., a consumer group sued state Insurance Commissioner Chuck Quackenbush, seeking to overturn his Proposition 103 settlement with the Woodland Hills-based insurer. The Proposition 103 Enforcement Project, headed by Harvey Rosenfield, author of the 1988 rate-rollback initiative, filed the lawsuit in San Francisco County Superior Court. The suit contends that the deal illegally shortchanges policyholders. Citing his own $232.60 rebate check from 20th Century, Rosenfield said it was $370.48 short of the amount he should have received under the formula developed by former Insurance Commissioner John Garamendi and upheld by the U.S. Supreme Court. Quackenbush defended the settlement as both legal and a good deal for policyholders.