WASHINGTON: Momentum is building for an IRS overhaul that could create the ultimate opportunity for revenge by corporate big-wigs who have faced audits. Former Treasury secretaries Nicholas Brady and James Baker surprised the nation's bean counters Monday by endorsing the creation of a private-sector review board to keep tabs on IRS efficiency, or the lack of it, taking the oversight responsibility away from the Treasury Department. The current Treasury secretary, Robert Rubin, is staunchly opposed because he feels the proposal would create conflicts of interest for taxpayers on the board. He is expected to put those sentiments on the record during congressional hearings on the plan, set to start Tuesday. In a multiple sound-bite show of support for the new system, House and Senate committees will be hearing a series of taxpayer horror stories calculated to make the evening news.