Your paycheck is about to be reshaped by the recently passed Republican tax plan. And the changes are coming so quickly that your employer may not have all the information needed to avoid errors that could lead to a nasty shock come April 2019. So Thursday, the Treasury Department released general guidelines for businesses and recommended that workers double-check their pay stubs using an online calculator, not yet available, when the changes take effect mid-February. Here’s the basic issue. Most Americans are expected to benefit from the tax cuts — as many as 80 percent, according to the Tax Policy Center. But the way the extra money will actually filter into peoples’ pockets can be pretty circuitous.