i added the gear myself by drilling the edge of my Olympus eveready case,in a specific position and then firmly attaching the case to the bottom of the ep1 with a tripod screw,
the gear used came from the transmission of a broken minolta rangefinder used for parts .
now there are more options for adapters of contax g mount, there is new one from
monza that look very well made ? and the RJ adapter from ebay [ i own the "small" gear version] is now available with a larger focus wheel , its second design
i consider the 45 and 90 mm contax g to be my two sharpest lenses, they are sharper than any nikon or voigtlander lens i own, or any other i have lens for that matter.
i own no lenses that outperform them on my micro four thirds bodies they are great
there are at least 3 different adapters for the contax g to micro 4\3 mount ,all with different designs ....prices vary greatly , and Im not sure which will suit you the best ,
look thru the forum here for links and on e bay and on the monza site and more info and take a look at them
my adapter is just ok , but not great , thats why i added the larger gear to speed up the focus , the tiny gear alone required many turns to go from infinity to closest focus , the added gear cut the number in half