I've just stripped and rebuilt a Speed Graphic. Unlike some other cameras that have focal plane shutters - the SG shutter isn't a module you can remove, it is built right into the body of the camera. So... you would have to remove the base assembly and any bits fastened to it (i.e: trash the camera) and then fix this heavy cumbersome box onto the back of whatever camera you wanted to receive the shutter.
Removing the parts of the shutter and remounting them in another camera sounds like a better project... but hopefully no one would trash a decent SG to do this - and an old one would probably need a new shutter curtain making anyway.
Seems like it is just one or two steps further to just building a focal plane shutter from scratch, copying the SG design? I did mull this over - as it would be possible to make it any size you wanted (10 X 8 or whole plate might be nice :-)
It seems to me that there is only one real obstacle, which is making the top gear train and release assembly. That needs a bit of engineering skill... unless one can be sourced in some repairers scrap box, somewhere?