As I said before, there is no way you can get both correct position and coordinate at the same time, using an official Chinese map, because of the government regulation.
The so called "offset correction file", ie. 006B082300.bin / GMAPPROM.IMG, is actually a coordinate offset file. By shifting the coordinate to the opposite direction, together with the offset map, Garmin will find the correct location for you. Now this file is part of the big IMG so you can get rid of the file and make things much easier. So basically, you no longer need the file if you use version 760 or 2010.21. But since you already have it, you may also keep it for insurance, because at least for me, keeping the stand-alone correction file with a integrated map won't shift my coordinate twice.
And it seems, at least what I saw on a Taiwan website, that the 006B082300.bin file only works for Nuvi / some Oregon models. So sorry I'm not able to test that for you. If you're using Mobile XT as I am, I can say for sure that you don't have to put the "correction file" into Garmin folder anymore.
Hope it clears your doubt.