Now on the antenna question I recommend the location the Tiger LLC. used and I have included photos showing that location, by using this location you do not screw up your headliner and the antenna is not shielded when your canopy is opened.I have seen several installations in front of the comm antenna that had to be moved because the hit the canopy when it is opened and closed and I also know of a tiger that can not get GPS signal till he closes his canopy this is very uncomfortable in the summer heat. I hope this helps and for anyone that does not get the photos I will post them on http://gpa.grumman-parts.com/

Good Luck
James Candeletti A&P
N4522Z N4515D
609-548-0959