I found some CAD plans that also have an alternate panel for the A-10/F18(or something) styled seat that does not have a center ejection handle.
(talking about the sides of the seatpan where the A-10 ejection handles should be, the surface should be horizontal).
Also thinking about using Jedi's plans for just the seat and maybe make some small changes. That might be a less expensive solution and his design looks nice allready.