I just looked it up, this one is a little different than I as an IA would normally expect- It looks like Avidyne is getting around this by calling the swap from a 430W to a 440 as preventive maintenance and no 337 is required- so yes the pilot could do it.
The pilot who performed the Nav/Com/GPS navigator exchange must log that activity in the airplaneās maintenance records (Airframe logbook). The entry must include information indicating the removal of the GNS unit, insertion and configuration of the Avidyne IFD unit, replacement of ICA and AFMS, negligible weight and balance change, dated, signed with pilot certificate number. Either use the sticker provided with the IFD or write the entry in manually. A sample is included below: The following preventive maintenance has been performed to this aircraft in accordance with 14CFR 43.3, Part 43 Appendix A and Avidyne IFD4XX & IFD5XX Series NAV/COM/GPS Navigator Exchange Guide, p/n 600-00316-000. Removed previously installed Garmin GNS4XX(W) (and/or GNS5XX(W)) and installed Avidyne IFD4XX (and/or IFD5XX) into existing Garmin radio tray(s) and performed functional checks per Sec. 3 and 4 of Avidyne IFD4XX & IFD5XX Series NAV/COM/GPS Navigator Exchange Guide, p/n 600-00316-000.
HOWEVER if you were swapping from a 430 non waas, that would still require a 337 and appropriate documentation. Even swapping a 430 out for a 430W requires a 337...