Mine are from a 2011 si, the 2012 seats are a different style, however in theory the installation would be the same if their not power. Basically what you do is take a dremel and grind the rivots off both sets of seats, your stock ones and the civic ones, then clean up the rails a bit. take your stock OEM legs off your old seat and bolt them in the car. After that, you set the new seat where you want it, and then tack one corner into place and eye it straight. With one corner welded, you can move it back and forth and have it set where you want. Once you have it flush with the legs, tack the rest. once the legs are welded, pull the seat out and reinforce each leg with a healthy weld. be sure to cover everything with damp towels! Also, I think its possible to drill and run a bolt through and not weld