Indus has changed meter in all variants from Xli to Altis, the sticker on the meter before facelift had a differnt code and now its different, Now the XLi/Gli also have the ECO light but its in active. Another member changed his Gli meter to Altises (Preface lift) and that was plug and play.
So my guess is its a plug and play device it should be avalible at dealerships as well as after market.
In Toyotas Owners manual there is a page in the end that say, ""Old meter change date and mileage" "New Meter date"
Since the Gli/At and Altis now are just cosmetic changes my guess is if some one get there hands on the cruise control steering that would also be plug and play.