i think its very do-able without any issues.
are u happy with ur seat cushioning? and just want to have electric adjustments?
if so then u can only swap the manual seat rail with the electric one, The actual seat with remain the same only the mechanism under the seat could be swapped.
even u can install the motors on ur existing seat rail with controls to move it, i saw that even manual seat rails have provision to install motors to move it electronically.