If you have the means to manufacture the pieces you need you could be alright. Assuming you completely gut the entire machine, bays and all, and can fit a motherboard, anything else is possible with enough planning and work.
You'd have to either adapt the keyboard or fabricate an adaptor. You'd be better off simply replacing the screen, but you'd have to fabricate adaptors for it as well to get a screen of a different aspect ratio to fit properly. You'd also have to fabricate covers for the unused ports on the side and cut out appropriate holes for the new ones (and likely fabricate extenders to get the ports from the motherboard to the sides). You'd also have to fabricate a way to deal with heat.
Is it possible? Yes, just about ANYTHING is POSSIBLE. Is it more work than it's worth? Almost certainly, unless you're really diehard about this project.