It will be some work, the mag metal recess is normally done by a router or CNC machine, and you will have to leave the mag bottom metal sticking out some. or chisel the recess out. Plus there's some in letting to get the action and barrel to fit. So it could be a lot of sanding, finishing etc.
It would depend on how much it costs you, you didn't say, and if your up to doing the work.
Mike.