I am building a Sea Rey and want to equip it for IFR flight since I am an IFR pilot and A&P. My Dynon D180 EFIS/EMS is sufficient for IFR instrumentation to the extent the D180 has the needed instrument functions in it. My plan is to use a certified IFR GPS/COM unit for navigation and communication and a certified transponder. I will also likely have a Garmin 496 or 696 VFR GPS mounted on the dash somewhere. Now for the question. Stepping beyond the minimum requirements supplied by the primary EFIS, what other backup or secondary instruments are people actually using to supplement the EFIS to be able to realistically recover from a primary EFIS failure in IFR conditions. For example, a separate airspeed indicator, altimeter, artificial horizon, etc. It has already been suggested that the Garmin 496 and 696 have a reasonably good primary instrument replication that could be used in an emergency. I have actually flown many practice IFR approaches (in VFR) using the 496 flight instrument page to see how it worked. It worked very well. Truth be told, it was more accurate and easier to follow than the old VOR nav/steam gauge even though it is not IFR "certified". I am very interested in hearing what someone has actually done with comments.
Thanks
Terry