I install the g3x for friends and have it in my own Rv. You’re going to love it. Looking through your list, you’re missing the 2 ap servos, plus don’t forget all of the associated install kits. You only need me module for the g3x which comes with the LRU kit. The gps 20 module does not come with a garmin 35 antenna which is required for the WAAS position source. I believe you would be better off nixing the gps 20 module and just getting the gps internal to the gtx45. It does include the antenna. Unless of course you foresee wanting to go IFR down the road, order the gtn625 for $5500 if garmin is still offering the package deal with the g3x. Then you can use it for position source. Also you only have 1 AHRS, the g5 would give you a battery backup and also give an extra ahrs if the GSU 25 went TU. But a Daniels afm8 off eBay and build your own harnesses. Way cheaper and you have the tools. I just built all of the harnesses for a rv8 I’m starting on in 5 hours. Feel free to pm me and I can add in any other details or answer questions. Also, the garmin x team is available to answer any questions and are happy to help.