My club recently got a GTN 650, G5 HSI, G5 PFD, and GTX 345 all installed in our Cherokee 180 for $28,300. We also got a few obsolete odds and ends removed from the panel, as you are doing. Labor was $9,000 of that price. The shop was Flightstar at KCMI.
We don't have an autopilot, so...