I suspect he relocated it to the correct position.
The factory position is inconvenient anyway; poor access for maintenance.
This whole thing is a bit of a mystery. I fully accept that EASA-reg owners will not want to talk about some off-the-books mod, but sometimes one gets info by PM. It could be that Socata tweaked the K-factor on the instrument to take out the roughly-20% error, leaving just maybe 5% or so and most pilots would not have discovered that, since they don’t check the totaliser accuracy regularly, if at all. Socata themselves are accomplished liars… on this very topic, 3 of their engineers telling me face to face in a meeting that they never heard of it, and then we have stuff like the inconel exhausts which are actually stainless steel.
That nobody in the avionics business is willing to inform us on a regulatory route, doesn’t surprise me at all. They tend to go “on strike” for a year at a time every time something critical of the business gets posted 
This is just shotting oneself in the foot, because forum participation brings a lot of business.
The FAA STC referenced earlier SE611GL was approved by the UK CAA under AAN 26779 prior to EASA being created and therefore the approval was automatically grandfathered as approved within EASA in accordance with the Basic Regulation.
There’s also another Shadin FAA STC SA1346GL approved on the TB20/21:
This was approved by the German LBA under ref 0366/1063 in 1993 so also remains valid.
the approval in germany was done by bac in cooperation with shadin…we have made some more…on 172-series…
if some one needs help w any jpi-stc and easa approval…just post or send me an email!
best
ingo fuhrmeister
