The International Cessna^® 170 Association

IFR certification of what? Are you trying to have a GPS installation certified?

The only certification for IFR is a petit static system check every 2 years.
Thats it. You are probably already having this done.

Of course you will need more instruments and navigation aids to fly IFR. Besides being installed properly and in working order and in the case of a VOR having a check every 90 days if you plan to use the VOR, no installation besides a GPS installation needs to be certified.

So John what specifically are you trying to do?

You guys got me to wondering about this subject and I checked with the local FSDO and was told, as others have been, that aircraft operating under part 91 do not have to have tso's radios to be legal.

So far I've heard results from MA and TX FSDOs. Anyone else out there in some other part of the country game to call their FSDO and see what they say?

I don't think it's a "consensus" type of decision...I just think your FSDO is wrong and needs to put it in writing so we can correct them in a meaningful way.