Will Frist's bill stand the way it is or can a 'guest worker' program be added to it?
As a matter of principle it can be amended. But Frist cut off a good deal of the amendment range with his introduction of a cloure motion, as well as calling for a DIFFERENT measure (lobbying reform) to be debated before the cloture vote on the Border Control bill.
As a practical matter, there is so much contention about the details of a suitable guest worker program, that bringing discussion of that to the Senate flor won't happen. The Judiciary Committee has itsel;f pretty well knotted up on that discussion.