We probably won't put in a Navigator any time soon and we're happy with our ADSB In solution. So we are considering the GTX 335. Plus its on sale right now. I was just quoted $7100 installed. We will be removing a KT76 transponder and putting the 335 in its place. Basically removing a KT76 and putting the 335 in its place. This quote includes a new pulse antennae and a new encoder as well. We will mount it up top where the old ADF(??) antennae post is still located. Does this quote seem about right / high / low / anyone ? Also, does anyone have recommendations on shops in the ND,SD,MN,WI,IA area that might be able to do this and beat this price by enough to justify the trip there and back?