I put the SP6 and SP7 under the left seat, positioned midway between the seatbelt bracket and the aileron pushrod. I used a hiking compass to choose the location, Now at full aft stick it does move the compass about 10 deg. At normal cruise stick position has no affect and matches the magnetic compass on the dash. I also use the MGL autopilot in 2 axis and it works fine in heading mode.
I dont have a photo of the modules mounted but here is the top hat bracket. For vibration isolation it has high density foam rubber sandwiched between the floor and the bracket. Bracket is mounted with solid aluminium rivets.
Steve
Sonex 892