The only problem is the bottom metal is different than the BDL bottom metal. The BDL bottom metal sits proud of the Christiansen stock, so the reverse will be true. The Christiansen bottom metal will probably sit well below the inleting on the MacMillan.
Sure can. No reason at all except for the added cost. I wanted to use the Christiansen stock on my Sendero, but the bottom metal was, I think, around $200. I just bought a McMillan instead and used the factory bottom metal.