Two Republicans briefed on the still-evolving plan say the proposal will be intentionally shy on specifics when it is announced, for fear of alienating moderates and the conservative House Freedom Caucus.
"They don't want to give people enough details to oppose it," a Republican involved in the months-long process tells CNN.
The plan, which is expected to start selectively leaking out on Tuesday on Capitol Hill and to lobbyists across Washington, is still being carefully pored over by House, Senate and White House tax experts.
The President is also starting to weigh in with far more interest, one person involved in the process said, which could open the door to more last-minute changes.
A version on Monday still contained instructions to the tax-writing committees on Capitol Hill to "find a way to raise more money from the top end," a Republican familiar with the document said.
It was unclear whether that language -- controversial in conservative circles -- would remain in the plan. But the President said earlier this month he is open to raising rates on some of the wealthiest Americans.
A new proposed corporate rate is expected to be included in the document, the officials said, but don't expect many other