Hi Kosa,
I checked the clearance and you have about 38mm under the slide as the nut is 46mm it's not going to fit under there.
Looks like the only way is too mount an alloy block in the normal position but make it long enough to come out the front a bit.
Drill a hole in it for the screw to come through. The nut will be out the front a bit and drop it down for clearence where the sloped part is at the front of the mill.
Otherwise these screws are great. A lot of guys here in Perth Australia have used these. Get the preloaded nut.
http://www.homeshopcnc.com/page3.html
Cheers
Bones