Senate Finance Committee Chairman Bob Packwood (R-Ore.) aims to bring his dramatic tax-overhaul package to a committee vote today and to work the panel around the clock in hopes of passing it by Tuesday, congressional sources said.

Senators received written versions of the plan only yesterday, and committee sources said the decision on a speedy vote represented an attempt to push the bill through the panel before opposition can coalesce.

However, Finance Committee chief of staff William Diefenderfer emphasized yesterday that Packwood would not force the matter to a vote without committee support. He said Packwood was prepared to work late into the night to build a majority.

"He's not going to break for tea and crumpets," Diefenderfer said.

The bill, a proposal to radically restructure the tax system, would almost halve the top individual tax rate -- from 50 percent to 27 percent -- while cutting the corporate rate by nearly a third, from 46 to 33 percent.

It would make up most of the difference by eliminating or scaling back a number of widely used deductions, and would shift about $100 billion of the tax burden from individuals to corporations by 1991, congressional aides said.

Packwood and five other Finance members worked through the weekend on provisions designed to win more votes and to ensure that low- and middle-income families receive the most tax relief from the dramatic rate cut, committee sources said.

In a key concession aimed at winning votes, they agreed to phase in over three years an anti-tax-shelter provision that originally was to take effect immediately, sources said. The provision would ultimately prohibit tax shelter investors from wiping out regular, taxable income with paper losses from those shelters.

The change meant a $10 billion revenue loss, and threatened to skew benefits toward the rich, but was balanced by other shifts in the tax burden, sources said.

For taxpayers who itemize deductions, the plan retains the full write-off of home mortgage interest, state and local income and property taxes, and charitable contributions, sources said. However, it ends deductions for state and local sales taxes, and greatly limits write-offs of medical expenses and consumer interest. It also does away with new Individual Retirement Accounts for taxpayers covered by pensions.

Packwood needs 11 votes from his 20-member panel, and was "very, very close" to getting them by late Friday, according to Sen. Bill Bradley (D-N.J.).