I have seen it mounted under the pilot seat outboard against the fuselage and it worked fine. That said, leading all the lines was much harder and there was not as much clearance from known and future electromagnetic influence. As such I would second Jake's recommendation. I think most are there and it gives you the ability to easily add components via the standard network cabling which could be quite short. Additions to consider are ARINC 429, transponder and future Dynon comm. With a bit longer cable you could easily get to the pitch servo.