yes its easier than you think , i used the base of the olympus eveready 2 pc case i drilled the bottom of the case and trimmed the snap botton to allow a tripod screw to affix the case tightly to the bottom of the ep1
i actually own 2 cases , one for the ep1 one for the gf1, the cams are so close in size the oly case works for either machine, but due to differences in the mount position relative to the cases in the 2 cams, the modification is specific to the ep1 ,in my instance
once the case bottom is affixed to the ep-1 and the contax 90 is mounted use the gear and a machine screw to guesstimater where you should drill the base of the case so the gear is snug against the focus wheel of the adapter,this time you are drillin front to back as the gear position and its screw need to be parrelel to the adapters focus wheel.......test fit the wheel and adapter and see if they function , on my first attempt i was off a little so i filled the wrongly drilled hole with a chopstick and cyanoacrylic glue and when set cut it off and began anew .......when the position is perfect put a little thin crazy glue in the hole to make the area arounfd the machine screw ridgid , the size of the gear you use determines how much more quickly the focus action is , with the gear ive used its about twice as snappy and also pleasantly has the toothed area of the secondary wheel[ gear] slightly below the base of the machine masking focusing easier still
the trick is to find a gear and a machine screw that are compatable , in my modification the gear came out of the base winder/ shuttercock transmission of a nonworking minolta 7s rangefinder , the screw tightness against the gear is critical , too loose and it engages poorly , too tight and its a chore to turn , i tuned it to a quarter turn and its perfect and works well , its more difficult to explain than it is to actually do !
i didnt use a drill for this , a dremel is the way to go for projects like these
the 45 is great , and the contax g 90 2.8 sonnar is the sharpest ,crispest lens i own for the ep1 its stuns me each time i use it