I'd let the illegal keep what he worked for --- but confiscate his owner's property to pay for the education, health care and any back legal wages owed to the illegal. All the lazy housewives who bring in illegals to clean their toilets and fail to pay them minimum wage, Social Security, Workman's Comp and the rest --- let their property be confiscated to reimburse their slave but first the taxpayers for services provided to that slave or family of the slave.
Constitution be damned, eh?